Smorgasbords are pretty poor IMO. For rocky terrain they're not bad, but on anything natural or soft they were useless.
The Geax Saguaro is possibly my new fave rear tyre! Really fast, way more grip than it looks like it should have, and it's not paper thin either. I used to love the 2.25" Crossmark, but sadly it's not available for 29ers, but the Saguaro is and it's a bloody excellent alternative!
Spesh Purgs are good on the front IMO, too much drag on the rear. A Ground Control can be ok on the back.
New fave front tyre is the Geax Goma. Imagine a 2.35 Single Ply Minion, but on a slight diet, faster rolling, and in an optimal 50a compound (rather than too soft/slow 42a or not sticky enough 60a), and that about sums it up! Can Zink has been putting these tyres to awesome use on his way to some of his most recent wins.