I'm considering getting a SIM free phone for my next mobile so was having a look around at SIM free deals.
Giff Gaff appear to be pretty cheap so I was wondering if anyone had any experience of using them (i.e. is there a reason for this cheapness).

Do they use the O2 network?

Yes they piggyback the O2 network so you should get decent coverage, though check the network coverage maps. You can also check the forum pages as to problems, and what users think of it. I was looking at Giffgaff myself when I was looking at buying the iPhone outright. They have a range of deals so will probably be who I switch to when my contract with Three expires.

I don't remember which forum it was on, but someone suggested googling 'Giff Gaff Service Dropouts' before committing to their service. I know they piggyback o2, but I don't think it's as simple as that.

The use O2's transmission network, but some of the other required bits are done on their own systems I think (for example, the bit that says your SIM has a valid contract against it). If O2's network goes down, you're stuffed and so are people on O2. If their own stuff goes down, you can't get a call or data in or out even if the phone has a full signal, but O2 users are still fine. If O2's back end stuff goes down, they're stuffed but you're still OK. It just depends if you think (O2 having fault A OR GiffGaff having fault B) is more likely than (O2 having fault A OR O2 having fault B).

They had some problems initially with keeping their bits up and running, so they got a lot of stick. I don't know if they've successfully resolved those issues now. It's definitely worth looking at the frequency of reported problems but I'd also pay attention to the dates on reports, it matters more if they've had problems recently than if they had them say a couple of years ago.

I have upgraded today and I currently have mixed feelings. I've just realised o2's coverage isn't as good and part of the reason giffgaff are cheap is that they don't have any support other than the website. During the transfer I have been using t-mobile's excellent support day and night. However, I have to remind myself, I'm getting a much better deal and saving £25 a month to boot.

It's strange how coverage buys loyalty.
When I was at uni, Vodafone always had the best coverage in remote areas. Ice been with them ever since without even checking current coverage maps.

I've been with t-mobile well, one2noone since 1997, I used to joke that if I stuck with them, eventually the coverage would improve. Now it has and I've left! Unfortunately their prices have gone up a lot too and money's tight these days.

I still assumed Vodafone had the best coverage, but my colleague pointed out it's now EE only this afternoon. I hadn't realised it would be such a big wrench to leave a mobile network!

I'm not surprised EE is currently best. When you merge two large networks,you're going to get a lot of base stations.

O2 will merge networks with Vodafone so the coverage shouldn't be an issue in the future.

As to Giffgaff, I've been using them for a year for my second handset. I use Blackberry on Vodafone for calls, texts and emails and Nexus 4 on Giffgaff for internet only. I buy £5 goodybag with 500mb every month and I haven't had a problem.

However, I've been following their forums and 2012 was a disaster in terms of reliability for users. Literally every week something has gone wrong on that network. The most common problem seems to be seamless transition from old goodybag to a new one upon expiry. In theory you should be able to reoccur them so you don't have to manually purchase one every month. But their systems are a mess so often the new one won't start automatically and you'll be using your credit to make calls, text and use the data. These problems take forever to sort as they seem to manually update your profiles if something goes wrong. They only way to comunicate with them is through message sent between you and agents, there is not phone number you can call.

So if you are looking to save money and you need reliability, you are better off with Tesco's network. What GG gives you is a flexibility. You can buy a different goodybag every month depending on how much usage you are expecting. Their PAYG rates for calls, texts and data are very good but be prepared for possibility of things going wrong.

If you do switch, I would advise not tu buy £10 goodybag, they are plagued with problems, buy the £12 one. Also, when you are joining, I would advise agains using a card to top up, buy a voucher instead, it's one less thing to go wrong.

I wouldn't switch my main handset to them but my friend has and he hasn't had a problem in six months. So have a look on their forum and make up your mind.

Here is the forum with all their problems:
http://community.giffgaff.com/t5/Servic ... tice_board

Hmm, interesting.
I must confess I'd completely forgoten about Tesco Mobile. Some of their deals look rather good actually.

The beauty of PAYG. You can change when you like, because buying one voucher commits you to nothing.

Well, I was going for a rolling 1 month contract sim-only type of thing.

I was going to do that last year, but for a one months rolling contract Vodafone were charging £20, whereas the same plan on a one year sim only deal was £13 per month.

I didn't want a contract, which is why I've ended up on giffgaff.

Yes a short PAYG contract might free me up to get a good deal on a new iPhone when I buy again. My current one was almost free with cash back, I would like another deal like that again, but I will need to switch away from Three to be able to get their deal again. Tesco or GiffGaff would be an option for a few months.