stock vs stock: GTiR would win hands down
BPU vs BPU: I'd have to say it'd be close, but the GTiR still has the t28 advantage
t28 vs t28: s13 no doubt
potential in the long run: s13, rwd vs fwd isn't a hard question to answer

w/ the growing popularity of the s-chassis, 240's are expected to have sr's now. For a more sleeper style, a swapped 200sx would be better. The main problem w/ fwd sr20det's is it's infamous 3rd gear.

check out www.sr20deforum.com for some fwd stuffs.
look up Miko Andreas, he's basically the fwd sr20det guru from miami. his posts are usually good.