I won't get into AT vs MT debate (as we all know how they end up
).
Imo the performance gap between both transmissions at least at this stage are so miniscule, that whatever choice one makes, it's one of purley personal preference. Put Dual clutch systems into the mix? And it will be very lopsided performance wise.
Some have mentioned that MT's give full control? True, though on the other hand neither does it curb mistakes (miss shifts, grinds and stalls etc.). AT's nowadays are pretty much idiot proof.
As the old saying goes... It takes quite a bit of practice and experience for a newcomer to be proficient on a track with a MT.. While on the other hand, a newcomer, can be pretty quick and consistant, in almost no time at all with an AT.
But out on the public roads (real world)? Other than personal preference and maybe mpg. Performance between the 2 is pretty much a moot point.
Either transmissions in the Z would be a fine choice. Btw... Welcome to the site.