Originally Posted by Dirty Dane

Exactly. But you can reduce the costs of it. If you send lots of traffic, you have the data to analyze. I can say this over and over again:
You can ask and read here and there, search on comments about sponsors, but the only thing you should trust is yourself (unfortunately). This is what you should do;
Spend some hours each week/month on your data. It is really the most profitable time you will ever spend! Heads up and top spot on your best converting sponsors (not ratios, but $/outgoing traffic) - get rid of bad sites (which could be good for YOU, if they just stayed out of nasty tricks). Make it routine and create a checklist of known tricks that you can use when choosing a new sponsor.
Its sounds very boring and nerdy, and it IS! But if you think biz you should do it. When I first started on this, the week after my sales rised 70% with same traffic.