Thanks for the clarification regarding the differences in the windscreens & mounts in the 650 & 400. I've never looked at a 650 closely enough because I don't have much interest in them.
For Kiwi Dave, you're right about the speeds of my Burg 400 and Silverwings. We regularly experience very strong winds in this area, which is why we have hundreds of the huge wind turbines all around us and the USAF trains it's pilots out of Travis AFB nearby. The strong cross winds makes it very difficult and dangerous to try to attain higher speeds on motor scooters and even motorcycles.
I'm not joking about the strong winds here... That's why I was so concerned about the severe flexing on my OEM Burg 400 screen and went with the Cee Bailey which is much better with hardly any flex.
BTW, I do not recommend that riders travel at high speeds on public highways. I did test runs on a long, straight stretch of road that had no traffic on it at the time.