I have a '12 SEL automatic w/ DCT and have occasionally encountered the "shudder" when it shifts between 1st and 2nd, the lunging when feathering the throttle in parking lots and the rollback, but as I said, they happen just occasionally and really are not very bothersome to me at all.
If the radio is above 2 volume, you can't hear the "shudder" at all, the rollback only bothers you when you don't expect it (ie. initial test drive only) and the lunging happened one or two times and can be mitigated by avoiding feathering the throttle. I haven't actually read anywhere that these traits are indicative of a failing transmission or transmission "problems", in fact the opposite. I don't recall the user, but he took his in to a dealer and was given a memo stating that these are normal characteristics of the new transmission. I chalk it up to the transmission shifting out of gear as much as possible to improve the mpg's (i'm no mechanic so i could be wrong, but thats what makes sense to me).
If I read on here that somone's transmission failed and had to be replaced as a direct result of these "issues" then i'll take action to rectify it. Until then, I love every inch of this car along with its quirky transmission.