I put a Hind Sight on my bow this past summer.
(which doubled the value of my bow... heh heh)
I've never shot with a peep, so I can't compare it to that... but I do like the Hind Sight. I can now play with my other bows and then pick up my 'hunting' bow and shoot consistantly with it.
It certainly doesn't limit the sight picture like I feared it might.
I give it a thumbs up!