I'm using the 1 1/8" dashboard for my Flexx bars. Problem I had with it was fit/finish for the plastic mount adapter. I ended up having to take off the metal wire clamps that are on the stock piece. I didn't realize this until afterwards, but there are instructions on the TrailTech website that tell you to do that as well. After that, the plastic adapter fit fine. It works well, and still looks nice. I only wish there was a way to utilize the stock adapter because the stock plastic (where the indicator lights are mounted) looks nicer than the Trail Tech plastic.
As far as the Vapor itself, I haven't installed it all the way yet. The magnetic bolt for the speedometer is too high up on the caliper to be read correctly if you install it the way Trail Tech tells you to. Another guy on the forum here said he just had to pick a different spot on the hub to drill and it works fine.
My buddy has a 450R has has the Vapor as well, and he is very pleased with it. It's nice to have a speedometer, tach, and he gets a lot of use out of the temperature gauge as well.