Just bought a custom 400EX, top end hot cam, Aftermarket Rev Box-I think 9000-9500 RPM limit, Air Box Mod, White Bros Exhaust-Complete System, and some other small things. Thing HAULS A$$. I Rode an 06 stock yfz450 about a week ago and let me tell this thing is equal to if not better! The power may be better on the bottom for the yfz450, but the hot cams top end cam helps the 400 throughout the mid to top. Neighbors started complaining only 20 minutes after I started riding. Sounds just as mean and aggressive as the yfz450. I also only paid $1900 for it and has less than 30 hours on it. Just need to find a place to ride as my backyard is pissing the neighbors with all the dust it makes. Any good trails in Washington State, in the Snohomish-Monroe area?