Running straight pipes are ok if you are doing the short bar hops with the harley gang. For long trips the sound is deafening though, and I mean that literally. Plus there are the noise ordinances to contend with.
Running without the goats belly and adding slip-on mufflers is very possible though. I have Harley dyna mufflers on mine (with the goat's belly) Before I had 27" fishtails without the goat's belly.
Note there is a BIG difference between sli on mufflers and straight pipes. Mufflers muffle, straight pipes are the sound straight out of the engine.
For anyone considering removing the goat's belly you might also consider an H pipe insert in place of it. It will help equalize the mufflers and provide some back pressure for performance.
You can also add a pipe section that will bring your mufflers out equally (stock has one muffler ending shorter then the other)
Patriot Guard Rider
2000 VN750 Sere (Serendipity)
1990 GL1500 (Ole Blue)
1986 VN750 EVie (project bike, heavy custom)
VROC # 11628 / 25000-H
ARVROC # 12 Coordinator and Crowd Control
OKVROC # 18 (H)
TNVROC # 45 (H)