InfusionSoft
InfusionSoft is the only affiliate backend that Matt McWilliams personally uses.
In conjunction with his Affiliate Portal Builder, it offers affiliates reliable tracking via cookie, contact record (email), and IP. In addition, the reporting is second to none. It is also the world’s best marketing software out there.
Note: This stuff is expensive and if you have the budget and are serious about growing your business, InfusionSoft is the tool for you.