I thinking of buying one for my quad. Anyone give it thumbs up or down?

 

I have installed a few D-A-J systems and they work pretty good and seen to be reliable.
Just make sure the bike s jetting is lean but with in 3 or 4 sizes of the proper main jet.
Oh yeah and make sure you use the snorkel and filter kit.

I would give um 4 out of 5. They are not perfect, but they are good for someone with basic mechanical skills that is not a jetting expert or that rides at different altitudes all the time.