Best Tier-2 PPC Search Engines?

Best quality traffic/least fraud

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I know we've had these discussions before on WW, but I'm still on the hunt for those elusive tier two PPC search engines which are not riddled with poor quality traffic from dodgy partner sites.

I can't recommend from our experiences, but ones that I would avoid are:

ePilot - paid for thousands of clicks on highly targeted search terms without even ONE conversion

GoClick - set-up geo-targetting, yet continued to receive flood of traffic from Romania, Russia etc. Support queries repeatedly not responded to.

So who are the good, the bad and ugly among the tier twos?