You should be fine removing it. It adds maybe 3-5 hp but I don't think there is a dyno onit anywhere. Mostly for my car it made the car smoother and I did not go into secondaries as often during city driving. My gas mileage also went up from 210/tank to 225/tank.
Just an exhaust pipe (str8 pipe) may be a cheap mod but it is very loud and sometimes not very clean. Perhaps a hi-flow muffler, backwards glaspack (just as loud but clean)or a bullet resonator would be better in the long run.
If this doesn't answer your question then trying searching for "resonator" and you will definitely find what you are looking for.
