When I got the phone it was already reset I assume since it started with the hello screen and the normal setup procedure. The strange thing is the wifi sync still lists his computer, and the itunes had his email listed, (Now I didn't enter my itunes account when setting up or it would have not shown up) but still not sure that should have survived a reset, nothing was logged in of course.
Anyway, I just set up on the phone and when I connected it to computer it never offered set up as new of course.
I put in my itunes account, my icloud account everything is active, t-mobile sim, find my phone, icloud, etc..
Logged into icloud on the computer find my phone shows up perfect.
Oh and this is just a backup, not my daily phone, so no worries. But I must admit ios 7 is running great for me, no crashes, good battery life, syncing and backups on itunes seem faster.