I'm so glad you posted this! I remember seeing these a while back and was super interested but then couldn't remember where the hell I saw them. (It's bookmarked now ) I haven't really heard any feed back on these but they look bad ass. I really want to install one of these on my '58 Trailblazer.
Scottie
Just got a response from Kevin in Shetland UK, one of our Ace members, on our Ace forum.
He says they work great. He has them on his Fireball Big Head Roller Rocker Bullet, and likes them a lot.