I installed Tony's kit about a month after getting my truck. It requires a full trans disassembly to replace a majority of the internal seals so they will hold up to the higher line pressures. I was one of the first 05s Tony did so we learned together on how to 'fool' the compter controlled aspects of the newer 48re. I am very pleased with the resulting shift chacteristics of the changes. My trans temps are lower and it really puts the power to the ground. BTW, some of the valve body mods are considered irreversable but you could probably use another body if you wanted to go back to stock. I have about 40k on mine and I wouldn't go back to stock.