I've read quite a few times that they don't fit well and your always chasing exhaust leaks,welding be a better option then the clamps.There's a post on the GL1800Riders forum by a member that just installed them who's pretty handy. I've never heard them live so I have no idea how they sound but there must be a video somewhere for what its worth.Seen an add for a bike with this add on exhaust. The bike is not close by to go look at. How much extra noise is there going to be? Any other negatives?