A do all bike. I have a CX bike and a mountain bike. I love my CX and the ease of adding racks and just the pure simplicity, strong build, good components and so on. But I must say as a do all bike I would choose the mountain bike. With a good pair semi slicks I can hammer out a good pace on almost every surface. Not as fast a CX, not as fast a road bike, but not a slow ride either. If forced to choose, the MB is good (not great) for anything or any condition we come across here in my area. On trails it is faster than a CX bike with more control, in snow the MB hands down with a wider tire and straight bars offer greater control. I am glad I don't need to choose one single do all but if I did the decision would be easy.