While the original question is a little old, the subject is always interesting to me. Thus, my .02:
I've found a good balance between cost/quality with the following scrubs:
Crabtree & Evelyn for men (very mild, can be used 2x day)
L'Occitane Cade face scrub (I now use this 1x day + Cade shaving cream)
Lab Series face scrub (somewhat more abrasive, not for daily use)
These are all in the $15-20 range and work well. I've tried some of $40+ products and they are truly no better than any of these.