Miata manuals (at least the NA, NB and NC generations I've driven) are very intuitive. It doesn't take much time for those shifters to become second nature. Same for most Honda manuals, e.g., S2000 and RSX. Those are probably the best feeling MT's out there.
The manuals in the FR-S/BRZ are not quite as good. They are notchier going into gear, the clutch has less feel and there's a slight dead spot at the top of the throttle pedal. As a result I have to think a little more about shifts around town to make sure they're smooth. The good news is with practice, you'll be shifting smoothly in no time. One thing that helped me is lowering the clutch engagement point.
http://www.ft86club.com/forums/showthread.php?t=8040
About the engine sound, I wasn't thrilled about it when I first bought the car. A Perrin catback easily fixed that, and I really love it now with a UEL header.