I will help you guys out with some info.
The joint still has the same "downfalls" of a typical double cardan. But as their webiste shows, it does have some "new" technology.
And about the Macpherson shaft. That was a one off custom pair that was made completely from 300M.
It does have a lot of promise, but Cornay is still trying to get a big order for larger sizes to bring the production costs down. They have the small ones on the Hummer, but none of the big ones are in much circulation.
I used to work for a company who was trying to promote this product, but it never took off for us either. I do however think it will take off in a few years(or less) now that off roaders know about it. Would be great for SWB Jeeps in the rear.
And there are a couple sizes they have made that are roughly 1410 size. I think they have a 1350 or 1330 size as well. But again, not in production.
And they can handle propshaft speeds. So you guys don't have to worry about that. I think between 5 and 6k RPMS depending on version.
I hope this helps clear up some confusion.
The website basically shows what they have done. Not what they can do.
Steve