I'd just look out for one with a good shell. All the technical problems can be sorted quite easily on the RST. I've bought a real shed a few months ago for about 400 pounds. Head was warped, had no oil pressure in the beginning (guess the piston rings were jammed somehow as it has been standing around for years) and nearly everything on the car was damaged somehow. Looked like it had seen some serious abuse over the years. Nevertheless it's running fine now, boosting 15 PSI. And I've only invested another 200 pounds to get it there. It's not a beauty but it's freaking fast.