i'm toying with the idea of buying an sr scope, heard some mixed reports though.
i've always used the higher end tasco scopes on my pcp's but at high mags their optics do go very cloudy. anything up to 12 (easily more than enough for hunting) is clear as a bell, get a bigger objective if your gonna be lamping / low light shooting.
had a few simmons scopes on my springers, never a problem with them.
bushnel come VERY highly rated here, and a lot use AGS. i think it mainly depends on budget more than anything else.