Anyone had much success with merchants datafeeds?

I've experimented slightly in the past with datafeeds usually on niche sites, and have always been able to generate a trickle of traffic, enough for each site to cover their costs etc.

I'm always experimenting with ways on making the content appear as unique as possible, but anything manual is just impossible, and automated methods are tricky to implement globally as of course the quality of feed and data contained within each one is different.

For my latest datafeed experiment i'm adding a section onto an established and reasonably ranking site, will be interesting to see the results once i've got some pages indexed, the longterm plan on this one is to implement hundreds of merchants datafeeds, for dual purposes, a) internal linking and b) hopefully more traffic.

Do these feeds allow you to include an affiliate code so that you get your comission and yet automate the process of inputting content/products on your site?