How many miles is TOO much to start modding a vehicle?

I own a 2001 Mitsubishi Eclipse Gt (5-speed) with currently 94,9xxx miles. I like the car a lot for its looks and its pretty quick out of the box. After asking some other 3g owners they say bolt on's have little to no effect on the cars performance, they say going n/a would be the best way to go. But before dropping 3k for RIPP mods supercharger I'd need to seriously consider if my car has too many miles for it to be worth it.( I prefer S/c over T/c because I hear the v6's have terrible wheel spin if you put a turbo on it) My guess is the car would have around over 100k miles before I'm financially stable to afford the kit. Many say that I should just sell my car and buy a WRX or SRT-4 but for how much I paid for the car + plus the kit It would be around the same price for a used car with around 100k miles and the 3g would be faster than both of those stock. I hope with the SC kit I can be around atleast 280 hp. So what do you think? Good idea or just a money pit that is a very bad investment?