First of all, I'm looking forward to any and all feedback on this specific topic. Basically, I'd like to know everything about using a US bought 3G tethered to ATT over in the UK on the 02 network which all UK iphones, presently, must use.

It appears to be an attractive possibility, aquiring an older 3G for around $100 from someone upgrading to the newer model, unlocking, and then using in the UK on the O2 network, which seems to offer less expensive plans (I've been told by Apple stores in the UK that the most basic plan runs only 15 pounds---and they were quite certain about that.) It looks far too good to be true.

So, who is doing this, and what's the catch?

Thanks,
Terry A. Gilliam