I hate to say it, but the Integra probably will have the best aftermarket support.

I have a SpecV (and an S13) and have been around a few S14s. The SpecV is an AWESOME daily driver. Ours is making over 170whp (and 175ft-lbs), has 80,000mi, and gets 24/28mpg approx. The only things that have gone bad were a MAF (CAI plus filled motor mounts plus balance shafts removed = lots of vibration and eventual MAF death), and the ECU (from a recall).

Otherwise, the car is awesome. Handling-wise, it'll run circles around most of the cars on the road (I've beat a TON of cars in AutoX with it....vettes, Miatas, Minis, etc). The Spec V's OEM Helical LSD and 6spd make that thing kick ass.

HOWEVER....if you don't want to swap or build the motor, you're limited to about 180whp with all of the bolt-ons.

The S14 is also pretty limited until you swap the motor (or build a KA-T). But you can get a full SR20DET motorset for less than $2500. So you could basically build a S14 with SR, suspension, and wheels/tires for less than what a Spec V costs. Then you have a turbo car that is easily upgradeable to >300whp.

Hope that helped a little.