Speaking of Mazda that is the route I choose. Anyways I prefer to mod under the hood vs. outside. I will tell you why.
1. There is nothing more satisfying than kicking a flashy car's ass with a sleeper.
2. With a body kit, fancy paint job, ect. you are just asking for a busted window and some vandalism. You might as well put up a sign that tells thiefs to break into your car.
3. It never fails that you scrape the underside of your car on something and when you have a fiberglass body kit, that just gets damned expensive to maintain. I can't tell you how many "riced out" cars I have seen around town with chipped/peeling body kits and quite a few that are just beat to shit.
4. How many of us can honestly say we could ever afford to mod under the hood and the body? You are looking at at least 15 grand to make any noticeable difference with the looks and performance under the hood.
realistically I would like a black 3rd Generation RX-7 modded with a Greddy T-66 or T-78 single turbo, straight piped exahust and a few other features. If I am allowed to really dream then I would get a 3-Rotor engine with a similar turbo configuration. The car has a very nice shape to it as is and the only thing I would do to the exterior would be to add a nice set of tires and rims. Oh yeah, A nice stereo system would go in it as well.