although noted 18 mpg from rx-8, during traffic, it's a heavy gass guzzler compared to z. and the break-in period in rx-8 is tedious. also not as decent looking as z IMO.... and 4 doors sports car?? and from what I heard, low torque in the low-end. but uncommon and different? definitely. 160 lbs lighter than z hatchback.
if you're getting Z, i'd recommend track if you're going for hatchback, otherwise get the convertible, they're all 2 seaters anyway.