I've never ridden a 500, but people say they are a pretty wide quad.  Does it still feel like it's going to roll on the flat track?

They are definitely wide but a well built Zilla feels like a fast Cadillac. When I say well built, I just mean kept up and everything is put together the way it should be. We're running stock shocks and the rear was rebuilt by Andy at MaulTechATV. We're going to have the fronts rebuilt and maybe have reservoirs added as well, but they were in excellent shape for now. Obviously some Ohlins or Elkas would make this feel even better. When you ride it, even at high speeds, the width just oozes confidence and doesn't make it seem as if you're going as fast as you really are sometimes. High speed sliding turns are a blast and it soaks up bumps pretty well. Compared to a less wide quad, you can take turns with more confidence because even if it were to begin to hook an want to get up on 2 or 3 wheels, the width gives you more time to react and a quick punch of the throttle will typically break the rear end loose and set it back down.