I emailed them awhile back about these exact risers. I believe they are a swap for the America risers, which I wanted since I have bars with a 4 inch rise on my speedmaster.
After a year I decided I didn't like my arms up so high. Nice on the freeway, not so good in the twisties.
So, I guess, the answer is Joker Machine is very good (I have their brake reservoir cover), but you need to decide how high you want your arms to be while you ride.
