I like Supertrapps. One for my KLX just came today to replace the old, rusty, nasty sounding Arrow that was on the bike.
Best feature is spark arrestor... Being able to tune the pipe is nice too! I paid $240; how much for yours?
I'm a dealer... so lets just say, less than what you paid. But not by much, $240 is a very good price if what you got is an actual IDS2 with a "quiet core".