Argotic Syndication Framework v. System.ServiceModel.Syndication

I'm investigating the Argotic Syndication Framework, and I'm pretty impressed so far. However, a lot of the current implementation--at least for RSS and Atom--seem pretty comparable to System.ServiceModel.Syndication. Does anyone have any opinions as to one over the other?

Here's my perspective after having followed both paths:

System.ServiceModel.Sydication

• is about 9 times faster than Argotic
• does not have rdf support
• doesn't have support for atom versions < 1
• doesn't have support for rss versions < 1
• fails with XmlException on about 30% of the feeds I give in "from the wild" (this is the deal-breaker for me)

Argotic

• hasn't been updated since Jul 2 2008
• is slow (see above)
• has very good support for all types of feeds: all version of atom, rss, rdf (as far as I can tell)
• is slightly harder to use than System.ServiceModel.Sydication; you need to determine what kind of feed you have before letting Argotic parse it, and then you need custom logic to deal with each of 3 different classes depending on the type of feed. In other words, you need to wrap Argotic before it's useful.