Got my micro-sim in the post from Tesco. I accidentally killed my 3gs whilst under contract so bought a sim free one from apple and asked Tesco's to send me a micro-sim. To start off with they said they wouldn't, but then they back-tracked, but this is besides the point. I had quite a lengthy and frustrating call with one of their customer care people, but during the course of our conversation he basically said to me that if I took my micro-sim out of my iPhone and put it in another phone for more than 10 hours, then my data allowance would be cancelled and I would have to ring customer services to have it re-instated ??? WTF???? So if I go out for a night on the pop, stick my sim in an old Nokia for fear of dropping the iPhone down the porcelain throne, I have to remember when I get back home to put it back in my iPhone otherwise I'll be charged for data useage ??? It wasn't until I hung up that I realised how crazy what he said was - I'll be phoning back in the morning to try and get clarity on this, surely they can't do this ???