I found a video about the model in the title here. Notable is that it has a centrifugal clutch like an ice model. It also seems to have a metal sprocket cover that now can really be called a clutch cover. Seems to be improved about chip removal from that area as my 536 model isn't too good in that regard. I have had my doubts about the two flats on a round that is perhaps 1/2" at most being able to handle much power for something getting called pro level. This is a screen capture from around minute 9. The guy has quite a few other videos as well, I wasn't searching for this when I found him.
