The I9100T is exactly the same phone as the I9100 save for a slight difference in radio output - you can use any firmware for the I9100 on a I9100T. The only thing you need to watch out for is the modem; I very much recommend you stick to modems bundled with stock roms released by carriers which sold the I9100T (at least in the first instance; particularly if you're using the phone on one of those networks). As you can flash modems independently of roms, this is no big deal.
If it's important enough to cause you grief if it's lost, back it up. No excuses
Trolling for thanks is lame
Does Samsung's auto-brightness implementation crap drive you to self-harm ? A solution !
Failure to search is the leading cause of male impotence on XDA
If you don't know how to recover if things go wrong, what are you doing flashing custom roms ?