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.
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