Yeah the upgraded seats in my club Q's are much better than the original seats.
The front of the S13 benifited from the addition of a strut brace, but the rear is fine without. Because mine is a non-turbo I can't say much about the turbo version which no doubt enjoys its LSD.
Basically the car is nice to drive but you would need some harder suspension, a camber kit and a strut brace for the front to get some real handling.
Interior is very nice, particularly for a car of the age. Much better than most of the cheaper modern cars.
Cheers
Adrian
PS. I was debating between a S15 and a R33 GTR... I know performance is a fair difference and the style but still new verse old and both the same price.