... and Verizon, too (well, OK only in one of VZW's newish "Band 4 xLTE" areas ). I did buy a $20/3GB plan from T-Mo when I got the tablet, and I switch SIMs around from time-to-time.
Don't know; didn't look, but normally I don't 'cause aftermarket ROMs on high-end Samsung devices tend to have missing features anyway so I never bother. I even like the standard kernel (despite it being non-OCed and sooo many revs back) that I'm not going to bother publishing an upgraded kernel like I usually do on the other tablets I've owned.
Received my P607t yesterday and requested an unlock through cellunlocker.net. They advertise 2-5 hours but I'm still waiting over 24 hours. How long did it take you? I'm concerned that this tablet is so new that it can't be unlocked or has a bad ESN. The screen is beautiful Btw. I do want to keep it if I can get it to run on AT&T.