My Bike Packing Bike is the Surly ECR so not a true fat bike - 3+ tires aren't quite wide enough for snow over 3 inches deep. But what I love about it and know my friends who ride "true" fatties concur is how forgiving the ride is on rough roads and trails. I have learned to trust the bike and can accomplish hills and rough terrain that I could never do on any "mountain bike"
Here is a shot from our S24O this past weekend. Click image for larger version. 

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