If you really want a pendulum sight.. then the TR Mantis is one of the best on the market. I normally don't care too much for the TR line of sights... for one I can't stand vertical pins... but that's just me. But the Mantis is a great sight. Very solid.. and doesn't make alot of noise like most pendulum sights out there.

Personally I use a Spot Hogg Hogg It... and couldn't be happier.