Incredible ride!
But your not gaining HP with your exhaust, your loosing a little actually especially using a slip on. Original exhaust were for noise suppression "Silencing for hunting etc" versus it just sounds cool noise makers.
The basic engineering behind these exhaust has not changed especially on slip ons. I can't remember where I saw a video at, where someone proved this on various quads in a .25 mile run. They used a couple of the top name brands "Yoshi was 1 of them" and ran stock machines up against machines with these exhaust. After several runs they proved that their was definitely zero gain, and some loss. This was just 2 years ago...
Now don't get me wrong, a lot changes in just 2 yrs. time. Maybe the engineers added some changes.
Where is your surround sound and TV's at?
I've heard dual exhaust coming straight from the engine adds a few additional HP. But I haven't seen anything proving this yet.
Cheers,
RiP