Haven't been around for awhile, took some time off to heal up! (: I am going riding this weekend up near Mammoth CA. I typically only ride tracks and was wondering what i can do to tame my 450 sound and compliance wise. I read tons of info last night with the search feature about pro moto/Dr D Spark arrester bolt ons, but am leaning towards a slip on. Anyone have any feedback on the White Brother E2, I know it is trail compliant, but don't want to spend the money if it doesn't add anything over the stocker for my core riding - Track. Also, does anyone know abou the sound testing they do up in that area - I know the stocker is about 103DB!!!! Anyone have any suggestions????