I just used the 310 kit to hard mount my new taco bars, and it totally eliminated movement, obviously, but the most noticeable difference to me is no vibrations. Wish I had done it to my stock bars before spending way more in grips to try to dampen it.
As far as working with the stock bars and risers, I don't see why they wouldn't. The top of the bushing is still even with the tree, and the bottom doesn't change from how much the bushing protrudes as the washer for it fits around the rubber sticking out.
Might send 310 an email asking them as well, they were super friendly and helpful with a question I had when I was thinking about buying the kit.