Yesterday I went in to a T-Mobile store and bought a prepaid sim for $10. While there I had the guy set up the account and port over a number from Verizon. Not once was I asked what phone I was going to use or the IMEI for a phone. Hell, they didn't even ask me for my home address. Not that I would hesitate to give either.
Side note; I am very happy with the $15 unlimited text plan. I have always hated paying AT&T as much as I was considering I mostly used SMS and wifi.
That sounds great - easy and painless. Hopefully, I'll have the same experience when I switch to T-Mobile in September.
Thanks for your responses, everyone!