There are similarities underneath between the two but tbh you are better off just going for the 944, easier to find, cheaper most of the time, plus they have more upgrades. Early cars have quite a lot of differences to later cars so stuff like the dash cannot be upgraded from the square style to the more rounded etc.

Keep the rst and just look out for a cheap 944. I'd love to see one fitted with a zetec turbo as I reckon that could be done good and not break the bank. If I wasn't going audi 5 pot with mine I'd be tempted.