Not to scare you, but I've been driving a stick for over 45 years and I have to say that the Z was the most difficult to master. As others have said, the engagement point is rather small, but I've found that if you take your time releasing the clutch pedal after a shift, it works a lot better. The Z does not like quick-shifting unless you are really pushing it, then it is fine.
After about 6 years of ownership, I can say that I almost have the smoothness down. There are, however, still moments where there is a little bit of a jerk (not the driver
) where I release the clutch too fast. If I were you, I wouldn't let these types of reports deter you from getting the 6-speed. Like most other things, "practice makes perfect"...and yes, you'll love the synchro-rev-matching (SRM) as well.