I think the straight pipe I have sounds nice. Even under hard acceleration its not that loud. Atleast the cops haven't pulled me over for it. Plus, civics don't know what the hell it is.
IDIOTS!!! But I'll be honest mine is not a true straight pipe. Just the rear muffler cut off and replaced with a pipe and a tip. Unfortunately, I don't have the money for the setup I want. Even then I might not be keeping the car that long. So... ask people to send you sound clips of their exhausts. Some people have them out there. Although we all know it never sounds the same way in person.
Good Luck! Remember to each their own! Looks are as important as sound.