It depends by the domain name mostly. In same networks a domain can convert 10 times better then another using same system (skimmed, popunder, click or else).
Then it depends by the country, nothing is as good as USA, follows north europe like NL DK NO SE.
Also some countries not sold as HD can be good, I like traffic from ZA (South Africa) as there's some good sales for cams there. New Zealand is not in HQ lists of many but is not that bad. Some sites like treafficshop sell you Hungary within "HQ traffic", I disagree
Also GReece is in all the HQ filters but I think it should no more be.
Finally I think the pay per credit card sale is outdated in tube and myfreecams era, I tend to value the traffic by regular free users, as in long run who stay lots there may buy.