Which japanese manufacturer do you like best?

[Elbow]

Mazda, because they have a great motorsport program.

[AFSil80]

I feel Mazda has followed the 'sports car' mentality the closest. I'm gonna go out on a limb here, so bear with me.

I'm a firm believer that TRUE SPORTS CARS are 2 door, RWD, 2 seater vehicles, and have a powerband that must be respected. Corvette, most Ferraris, TVR's, etc.

That being said, look at the lineups of each Japanese manufacturer's flagship cars so we keep this on topic:

Toyota:
Supra (MKIV, for the sake of argument)- 2dr, 2+2 seater, FR - Toyota promoted it as a GT car, not a sports car. Hard to say, due to the car being overengineered, and being one of the few Japanese cars that has been able to repeatedly embarrass higher-end European cars. Plus it held the C&D braking record from it's debut in 1993 until the Carrera GT debuted in 2001. Tough call, but I'm sticking to labeling it as a GT car.
MR-2 - 2dr, 2 seater, MR - Entry level sports car. Good power, superb handling. Again, overengineered in every aspect. Probably one of the few good looking street terrorists out there, but still lacks power from the factory.

Subaru:
STi - 4 dr, 4 seater, AWD - Read EJ25run's post.

Nissan:
300ZX - 2dr, 2 seater and 2+2, FR - Tough call, due to both seating configurations. I'd lump this one in with the Supra in the GT crowd before deeming it as a true sports car.
350Z/370Z - 2dr, 2 seater, FR - Sports car. Makes decent power in stock form, but we all know these cars will throw down with forced induction.
GT-R - 2dr, 2+2 seater, AWD - GT car. The Skyline family has ALYWAYS been sedan based, and like EJ25run said about the STi compared to the Impreza, the GT-R is nothing more than a standard Skyline on steroids. Not a true sports car.
240SX - 2dr, 2+2 seater, FR - Not a sports car. Entry level at best. It was never intended to have blistering high-speed performance.

Mitsubishi:
Evo - 4dr, 4 seater, AWD - Same thing as the STi and GT-R. Hopped up base model built to win races. Not a sports car.

Honda:
NSX - 2dr, 2 seater, MR - Sports car. Good power, responsive, lightweight chassis. While it may not have been the FASTEST car out of Japan, it's still a terror on the race track and street.
S2000 - 2dr, 2 seater, FR - Roadster. Makes good power, but is still too underpowered to be classified as a sports car.

Mazda:
Miata - 2dr, 2 seater, FR - Roadster. Lacks the power to qualify as a sports car in my books. Entry-level club racer at best.
RX-8 - 4dr, 4 seater, FR, however, Mazda proclaims it as a new-age sports car for the family. IMO, they have succeed. Lack of low end response aside, it's prowess is undeniable in the turns, and it's behavior in the upper RPM's.
RX-7 - 2dr, 2 seater, FR - Sports car.

In my honest opinion, the RX-7, NSX and Z-car's are the ONLY true sports cars to ever have come out of Japan. Now don't get me wrong, I absolutely LOVE the Supra. But it was intended to outhandle it's competition on the race track, and it succeeded in doing so until the GT-R came along.

So yeah, let's get a REAL debate going on now. Again, this is all my opinion, I didn't build em, so don't take me TOO seriously.