My take on feeds is that they are great in the sense that they get your content 'out there' using an established network that to some extent is distinct from the normal methods (in particular searches on SEs).
The downside, from an SEO point of view, is that it is even more dependant on relevancy and freshness than traditional approaches.
So you increase your reach, but have to invest more in terms of interesting and updated content. After all a feed is meant to be used to send changeable data to a user, as opposed to the tradtional method of searching to see what's out there. The classic example of this is of course news headlines. The attraction of a feed (for a user) is that you can see the most up to date stuff at a glance. The challenge for someone like yourself is to have that data updated regularly enough that it is attractive.
In my view it is a mistake to assume it works in the same ways as traditional SEO (a source of extra links etc). The overhead of finding fresh material may not be offset by extra visitors.
That said, it does no harm, which makes it attractive from an SEO point of view.
I think the best advice for how to use RSS for SEO purposes is to use it as it was intended, namely a channel for information, and not an end in itself. Using RSS for a list of product pages, for example, is boring to end users, and unlikely to find subscribers. An RSS feed used to publicise commissioned articles is much more useful.