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As far as the trust factor is concerned, however, my own personal most trusted of all is Shareasale, since they have a firm anti-parasite stance, which impacts the bottom-line income of both merchants and affiliates alike.
Personal track record and history:
Parasite-ridden merchants and networks = low to zero conversions and ROI for my efforts.
Parasite-free merchants and networks = consistently satisfactory conversions for my efforts.
Additionally, I don't believe that merchants want to pay "parasitic third parties" commissions for their own type-in, direct or PPC traffic not directly generated.
Judge for yourself and take it from there.
That said, if you are an affiliate (web publisher), you'll want to seek out all merchants whose products match your web content, and consider which to include as "pay-per-sale" advertisers. Often that will include one or more merchants from each of several networks, plus one or more "independent" merchants (who operate their own program without any network).
I personally don't like Commission Junction or LinkShare, and would not recommend either to a merchant or affiliate, but if you have a web site about widgets and the biggest widget-merchant has its affiliate program through one of these companies, you'll probably need to work with them.
The major affliate networks (not talking about CPA networks) are Commission Junction, Linkshare and Performics.
If trusted you mean parasite free or close to it. Then Shareasale, Avantlink, Affiliate Future.