I write a lot of mobile ops on Ciao, and am a notorious gadget freak. I do drive my boyfriend insane with my constant buying, selling and upgrading, but technology has always been something that has interested me, even since my junior school project on the network of bulletin boards that was soon to become the internet - and that was a good 14 years ago!

So when I got to the age where I was allowed my own mobile, I went through a few different networks and cheap phones. My first was Vodafone, and when the aerial fell off, I went to my local Virgin shop to check out their phones. In those days, Virgin shops stocked a lot more refurbished handsets than they do now, so I actually got a Philips Savvy for £25 with calling credit and SIM included. I only switched away from Virgin when I made new friends who all had mobiles and were mostly on the Orange network (as it's cheaper to call on your own network than to call 'cross network' mobiles).

Even though I have stayed with Orange since then, I can still see the benefits Virgin mobile offer. However, their service does have some small but significant differences to most other mobile companies, and that's the reason I won't be going back to them fully at the moment - although I do have a Virgin phone as a spare.

--> ABOUT VIRGIN MOBILE

Virgin Mobile is a so-called 'virtual' network. Rather than operating their own mobile network as the four major UK networks do, Virgin rent space off T-Mobile (formerly One-2-One). In other words, if you can't get a T-Mobile signal in your area, switching to Virgin won't make any difference at all, as Virgin runs on top of the T-Mobile system. And remember, even if your friends are on T-Mobile and you're on Virgin, both networks still cheekily charge for cross-network calls from one to the other.

Other virtual networks include Tesco Mobile (who run over o2) and Fresh.

--> CALL CHARGES AND WAYS TO PAY

You can pay for your Virgin calls two ways. They operate the standard Pay As You Go system, where call time is increased by buying vouchers, using an E-Top-Up swipe card, or registering your credit or debit card. Interestingly, you can use your registered card over the phone or - and here's the good bit - through the website. This is a really handy feature, and something Orange definitely don't offer.

The other way to pay Virgin is to use Direct Debit. This involves a credit check, as calls are paid for once a month after use. If you want to take your phone overseas, you have to register for Direct Debit before you go - so this is worth considering if you're going on holiday but don't have a bank account.

Apparently you can also use the two systems combined - register for Direct Debit, but continue to top-up to keep the account in credit. Definitely a nice idea because effectively you'll never run out of credit on your phone. This is a great reason to use Virgin at least for a back-up number for emergencies.

--> NETWORK FEATURES

The world of mobile communication is advancing now, with picture messaging, GPRS, and even video messaging features designed primarily to make us spend more on our mobiles. For some reason, Virgin is the only network - virtual or otherwise - that cannot yet support these new technologies.

GPRS, for example, is a cheaper way to access the internet on your phone. Instead of paying by the second, you are charged around £3-£6 per MB downloaded, depending on the network and tariff you choose. Virgin does not offer GPRS, even though many of the phones they sell can and do support the service. So you're still going to be paying for WAP by the second, and given how slow the service can be, that's a real pain if you want to check your email often, or download ringtones, games and pictures.

And for the same reason, you can't send or receive picture messages over Virgin, which is why they rarely sell camera phones or place a large emphasis on anything other than texts and calls. It's probably also why the network are so much cheaper than any other Pay As You Go.

--> CALL CHARGES AND TARIFFS

Luckily for me, your humble reviewer, there's only one tariff on Virgin, regardless of how you pay, who you call or how much you use. So it's relatively easy to work out whether Virgin is the right network for you (and even easier for me to summarise their services!)

For the first five minutes every day, as long as you are calling another Virgin customer or a landline, you pay 15p per minute (billed by the second of course). After that, it's a standard 5p per minute charge for the rest of that particular day. There is no off-peak or peak time band to consider.

Calls to another network cost 35p at all times which is about the same as every other network. Shame these are not a little cheaper, as Virgin has a relatively low number of users, and most of your calls to mobiles are therefore likely to be cross network.

In a similar vein, texts to other Virgin mobiles are cheap - 3p, without any need to buy bolt-ons or add-on packs, as with o2 or Orange. However, consider how many of your friends really are on Virgin before you rush to take up this deal. Texts to any other network are 10p - although that's 2p cheaper than Orange, you've not got any option of reducing those costs if you text a lot.

Roaming charges on the Virgin network are generally considered average or cheap, but bear in mind the requirement of Direct Debit and make sure you set that up before you leave.

--> CUSTOMER SERVICE

The o2 network currently charge their users 50p a minute to sit on hold and discuss account problems. Oh, you can email them of course, but they never reply. Orange are better, if you can find their 'secret' 0800 customer service number, but although the operators are helpful, you rarely get the same answer twice - and if you call from a PAYG phone you could be paying as much as 25p a minute to talk to them.

Virgin are a different kettle of fish. Over the past two months I've had customer service problems with Carphone Warehouse, BT, TalkTalk, Equitalk, Dixons, 'Three' and The Link. With Virgin, I have not had any problems at all.

I've phoned about my account, to order products, and to enquire about services. The staff usually answer within a few seconds and if they're going to put you on hold they tell you how long for, why and ask if it's OK to do so. All advisors really seem chirpy and happy to chat informally about the products, and they have impressive knowledge of their products and their computer sytem - the advice you get is always consistent. If they need to call you back, they tell you how long it will take to do so, and they actually DO call when they say they will.

Calling Customer Services costs a flat rate of 10p from your mobile, or you can call at 0845 rates from a landline. I don't begrudge paying them 10p for a call that might take 10 minutes. You are clearly warned about the charged and asked to confirm that it's OK before you're put through. Fantastic.

--> OTHER ADVANTAGES OF VIRGIN

1. Voicemail is always free, as long as you have some credit. A big plus if you tend to lose your phone a lot, keep it switched off, or mainly only have a mobile for incoming calls.

2. When you've bought your phone, you'll benefit from registering with the Virgin website or over the phone. Not only can you view your balance and calls - yes, even on the voucher system! - you can also top-up online, or access other member benefits. You can upgrade your phone for £10 less than advertised as long as you want to keep your current number, and buying direct means you also get a free £10 top-up thrown in. Even better, phone up and buy a joining pack or phone for a friend, and you'll earn £10 credit just for recommending them with the Glue scheme.

3. If you like to shop in Virgin megastores, every time you spend £10 you can earn a £1 airtime voucher, simply by showing the checkout assistant your Virgin phone. That's effectively a 10% discount on your purchases, and can be earned on anything in the store except for top-up cards.

4. And when joining Virgin, you can also move your current number with no hassle. Simply ask your old network for a PAC code, and phone Virgin to port-in your number. The number is moved from your old operator to Virgin in around 7 days.

5. But the biggest plus of Virgin has to be the free unlock scheme. Once you've spent £30 - which includes any credit you get on your new SIM card, and any free credit from the Virgin site, Glue or Virgin Megastores - you can email the Virgin staff and get the unique unlocking code for your phone.

--> CONCLUSIONS AND ALTERNATIVES

If you need a phone mainly to call and text people, Virgin is a good choice. If you only really need to call one or two people and can persuade them to move their numbers, Virgin is absolutely perfect. Cheap calls, relatively well priced phones, 3p texts and all the additional benefits I've listed above.

However, if you have friends on other networks, you're always the first to try new technology like photo messaging, or use WAP or email a lot, Virgin is probably no better than any other network. The lack of GPRS may cost you a lot, and restricted features might be frustrating. And you'll also be calling most of your friends cross-network if you call mobiles most of the time.

What about the alternatives?

Heavy texters or WAP users could consider an o2 Online SIM which gives you 300 free texts and 300 WAP minutes or GPRS pages a month. All you have to do is add £10 call credit at least once every 28 days.

Moderate texters could consider an Orange Text Saver pack which gives 5 free texts every day for a year.

I certainly wouldn't recommend T-Mobile for anyone who spends less than £20 a month, as their call charges are horiffic. If you do spend that much, you're probably more likely to want to move to a contract anyway,

I hope this op has been useful. Let's hope Virgin can incorporate GPRS too - if they do, I'll be the first to move my number to them for good.