Actually from what I've seen, the VTEC (H22A) has the most potential for turbo's and mods. The S (F22A) is quite limited with what it can you can upgrade. I'd go with the VTEC, it has much higher stock power than S (F22) or Si (H23). I got the S (F22) and really wish I didn't. So far, I've heard VERY little about turbo's on the F22A.

I jumped at the first nice Prelude I could, I kinda regret not getting the better one. I love my Prelude, but now I'm looking to engine swap with an H22.