Hmmm. Weird, that my '12 got new clutch packs and TCM under warranty, but then I'm in Canada. The warranty on both had been extended, as well as the transmission input shaft seals. They also replaced the clutch forks as they said they were "rusted and sticking" which was not covered under warranty.
I did not have any notable shudder. Driveability seemed fine to me, until something went "bang" as I was pulling away from a light, and it started shifting worse them my 14 year old daughter the first day I took her out to teach her to drive stick. (In the Supra with a 6 puck racing clutch.) No reverse was an unpleasant surprise when I couldn't back out of the parking space that I'd pulled into to check things, but I could make it go forwards well enough to drive it back to the dealership.
So after all the stuff was replaced, it seems to drive the same to me.