I've got the Kuryakyn ones on my 06 SG's. They have been on the bike ever since I bought it new. The only issue I have had are the screws rusting and the little rubber washers deteriorated. I went to West Marine and got some cute little Allen screws and some nylon washers and have had no problems. The air flow is good and is noticeable when shut (no extra air). I also had the Kuryakyn heat deflectors for the rear cylinder. They are good, but I recently replaced them with the HD ones. I like them a bit better because they fit tighter in. The only problem with them is the installation with the engine in the bike. If you don't have patience and small hands you better let someone else do it, and keep an eye on the hardware when it gets away from you.I have large hands and they bled a little, and the hardware that got away is still away, never found it. More than what you wanted but that's what happens with me.