Which is of these two is better for ppc campaigns for affiliate marketing?
Adwords Stricter on the quality of your website and the type of products you're advertising. Can be very expensive depending on niche. Much higher volume.
Adcenter Lower volume but from my experience the clicks convert better. Generally less expensive. Infinitely better support.
A successful PPC campaign will run well on both of them but for quicker impact try Adwords first.