PopAds (And Other “Low Quality” Sources) For Cheap Traffic: Yea or Nay?

I was recently watching some videos on different ad networks, and one I came across was PopAds. It seems like despite the traffic you're going to get probably being quite low in quality, it seemed that one could potentially get thousands of impressions for really cheap.

Even if only say, 1-2 out of 1,000 were to make a purchase, if I only paid a few bucks for those eyeballs on my site, this should actually be quite profitable overall, shouldn't it? What are your guys' and gals' thoughts on this? Something to try for a bit to see how it does? Or something best avoided altogether?

Thanks!