CJ Affiliate, formerly known as Commission Junction, is an affiliate network and online advertising agency headquartered in Santa Barbara and owned by the Publicis Groupe, a French PR and advertising company. CJ Affiliate's technology offers affiliate personalization, cross-device customer journey campaign management, and a content monetization suite of products for publishers.
CJ definitely has the largest pool of publishers and is well built out in terms of features. However, it does appear that they have a lot of dead weight in their pool which is something that their competitors claim they have solved.
They are pretty similar honestly we only use different options because there are different companies promoted on each one. the search feature in CJ affiliate is not as easy as Awin.