I can't see myself replacing the FiST with a new car. It does what it does so much better than the competition. If I were to get a new car when this one is paid off, it'll be in addition to the FiST, which will probably remain a daily. At that point, I'd be looking at options like the Cayman GTS, 911 Carerra S, BMW M4 Coupe, or Nissan GT-R. If I'm feeling cheaper than that (or simply can't manage those) I'd grab an M235i--The M235i being the only thing I could even consider trading the FiST against, and I wouldn't.
But, considering I really, really want an E46 M3 project, I might not have need of buying new cars for a long...long time.