I see a lot of phones on ebay with bad esn's. Does a bad ESN take away all functionality of the phone or does it just render the phone part useless? I would love to get an S3, HTC One X, HTC Evo 4g LTE to use for its features. I won't ever need to activate the phone, but I would use for music, gps, wifi, Google Play apps and games, etc. Good idea? I'm considering a tablet, but maximum portability is what I'm after and the 4 inch+ seems to fit the bill.