Well there's a few more factors to consider. If you do decide to do the pipe and filter you may have to rejet your carb. Rejetting is easy for someone who knows what they're doing, like a scooter mechanic. If you've never done it before then its a pain in the ass. So your looking at about an hour at the shop, so tack on $100 for parts and labor. You'll be losing the awesome fuel efficiency you once had. Have you already done the weights and varietor? Maybe put in a performance clutch with lots of padding? Those are your quickest return for your buck. But all in all, I know someone who did all these things to his BW and he hauls ASS! He went with an MRP pipe and it doesn't sound any louder than stock.
