WR450F Evolution Full System****Fit and Finish: NASA envies this pipe. The craftsmanship in Akrapovic's exhaust systems are first-rate, and anyone with a keen eye for high-quality welds will appreciate it. Install gets a B-it's more involved than some because there are more pieces, but it fits exceptionally well.On the Trail: This pipe addressed the sign-off top-end feel that is characteristic of the stock system. It has good, smooth drive like stock, until the mid, where it is boosted with strong power in the upper mid through the top-end. It lets you run the gears longer than stock. The delivery is smooth and not overly exciting; it's always usable and linear. It may not be a rip-your-arm-out-of-their-sockets monster, but it does the job extremely well. The Akrapovic is a favorite for its mix of beauty, durability and performance.