I’ve been hand building disc specific cyclocross wheels for a couple years now. We all know about the increased stopping power and better modulation of disc brakes. Disc rims are also lighter because they don’t have a brake track, so they spin faster. I build them with both 130 and 135mm spaced rear hubs. 135mm is the standard mountain bike width so there are lots of hub choices. This seems to be the cross choice width of the future. 130mm spacing is road/cross width but some disc cross bikes have 130 spacing. White Ind and Velocity both make 130mm 6 bolt disc hubs. For those crossers needing a disc hub with a Campy spline, yep I have those as well.