Are my affiliates helping or harming me?

[theLotter]

I have a very strong affiliate network.

Currently all my affiliate links go to a subdomain with a 301 redirect to my site.

I have somewhat of a linking profile besides affiliates, but it is not as strong as the affiliate site.

Are my affiliates enhancing my linking profile and helping me?

Or

Does it look to Google like I am benefiting from "paid links" and they would prefer I add NOFOLLOW or a 302 to my affiliate links?

Thanks for your help!

[stereo69]

Here an interesting article:

http://www.seomoz.org/blog/getting-seo-value-from-your-affiliate-links

Is it stil up to date and good practice to create a site for each affiliate and then use rel canonical to pass the link juice to the main content page?

Can somebody give some more resources how to turn affiliate links to seo frendly links?