Ive had my 700xx for about 8 months now. So far I have only road it on the sand dunes, still getting used to not having a straight axle. Ive been thinking about a pipe and efi controller but I don't want to spend the money if there's only a slight improvement. I also don't want to exceed 96 decibles. Im also wandering if they make Haullers for 12 inch rims. Thanks for any info.