I use a Western Flyer as an EDC with a Surface 3 in a Cache. I will be upgrading to a Surface Book 2, either the 13.5" or 15" version, I'm not sure which yet. I still have a size 1 Brain Cell I may use for EDC if I go with the 15", but I would need a Cache for travel with either the 13.5 or 15 inch versions. Anyone have experience with this setup in the WF and which Cache will fit either machine?