i use the MFA filter a lot, although it hasnt really had any effect on my revenue, probably its the niche itself that is sucky
It does help to use it. Comes in hand for thise low paying advetisers. You can't blame them for being cheap. Ads are expensive.
The problem I see with AS is, you are forced to look at your ads in order to start filtering, and at the same time that messes with your impression count. Or does the ad preview tool avoid this?