oh and another few comes to mind:
people will say this and that sponsor converts best for them. stick to my advice: what works for them might not work for you. you don't know how they push their traffic there and where do they get it from.
don't fall for good conversion rates people will post. they mean shit when you don't know what traffic and marketing methods were used. if traffic is very filtered and very productive you can have conversion ratios even as low as 1:25 (I had em for months - won't tell where and how tho
) and you can have them 1:1000 and that could be good (if you can covert the lowest possible quality traffic at that ratios)... conversion ratios are relative... what's important is how much money you make - that's the bottom line. remember that.