A couple months ago, I ordered a Mukluk 3. This was intended to be a training bike for the upcoming race season and for commuting on snowy days. I am surprised at how nimble yet stable this fat bike is..... it absolutely handles snowpack and icy trails, but it is also amazingly fun when conditions are dry.
It rolls over just about anything and feels lighter than you would think. It doesn't accelerate really quickly and I don't break any records on long climbs, but those are it's only real shortcomings.
It is a really cool thing to ride a fully rigid bike for the first time in years. Clearly, it is not made for big drops or wicked rough trails, however, the Nate tires inflated to around 8psi smooth out most of the trail chatter. The traction is unrivaled.... it is like riding on velcro.
Overall, it has become my favorite bike to ride.... in fact, I have taken my FS bike out much less than I did last summer!
Also, the BC.com build was superb. The only thing I had to do was a minor adjustment to the rear derailleur and tighten the headset after a few miles. This thing rules!