I have the Vital Bow Gear Camelback pendulum sight and think it's pretty cool. I haven't had any problems with it at all either. I have it sighted in at 20 yards on flat ground, and also tried it out from up on my back porch roof aiming down at 5 yards and it too was dead on accurate. I haven't tried it at 30 yards from an elevated point (yet), but will try it soon.

Some people don't care for pendulums, others like them. I got mine out of curiosity and so far, I like it....