fearlessrick - 4:16 pm on Aug 23, 2010 (gmt 0)
I get about 90k unique visitors a month and massive (Google says 100,000, but my adstats say 400,000) pageviews off those and direct advertisers work well for me. Also, nobody complains that I also have Adsense, plus another network (pay per impression) on the pages.
Your ad rates may be competitive to what G or other networks charge, though I have found that everybody seems to have a different idea as to what is reasonable and what is not. Most advertisers will want direct links, meaning you have to know how to use div tags and create text "boxes", but once you get some advertisers on your site, others in the niche will take notice and contact you directly.
I have found that it's definitely worth the effort, as those extra bucks pay for extra stuff.