Seems to me that, from a strictly performance standpoint, the best transmission is the one that will get you through the quarter or around the track the fastest. Doesn't matter what's on the inside or what it's called.
For a DD, Jordo! sums it up very well: "personal preference." I've had several manual transmissions over the years and thoroughly enjoyed driving them. I still prefer an auto in my DD.
When it comes to automatic transmissions, the 370Z has the best I've driven (but my experience is limited). Manual mode is fun and I have no doubts that it can shift faster than I can shift a manual.
YMMV
