Do a search, there are several threads that discuss them.

I had one on my new Switchback several months ago. Initially, I liked it, but as I used it more and more I had some reservations. For me, I felt that there were two detractors. First, I felt that my shooting was far more suceptable to torque using the hindsight. I think this is because of the shorter sight radius, (similar to a gun, a longer sight radius generally will result in a more stable and accurate firearm). For me, I tended to group well, just left or right some days if I was not very particular w/ my anchor points and grip. The second thing I personally did not like was that I felt that the "X" part on the rear sight tended to obscure too much in low light. When set up as the factory says, with the x on your mid range pin, the cross hairs tend to hide more than I was comfortable with. I had several low light situations where I drew and really had a problem picking out details on the deer, shoulder point/line etc, that I use for aiming points.

Long story short, I took the hindsight off, put in a good peep w/ a sword twilight hunter, .19 pins sight and am back to shooting golfballs at 20 yards and baseballs at 30.

BTW, I gave mine to a coworker who tried it, he took it off and gave it to somebody else.

It might work well for you, good luck.
Hank