Where are you located that Rallycross is even a factor in your decision?? To my knowledge from the 757, and 804 areas there could be 2-3 Autocross events a month and maybe 1 rallycross every other month. Also car setup of a Rallycross car and an Autocross car couldnt be farther apart is you want to be competetive.

E30 all the way if this is a car you would not be too upset is you "wad it up". Parts are every where, new and used, and they seem to be very cheap. Cars can be had in the $2K-$3k range and even less if you are in the right place at the right time.

Subbys are over weight, and over priced. At like $8k-$10K for a car with no mods.... Not any thing I could brush off if it were to be waded up.

BUT!!!! For you to get a more informed answer you need you better describe your goals, and budget. The cars you have asked for oppinions on are very different, as too is the types of events that you maybe taking them to. So at this point every one is just shooting in the dark.