If we are talking FPSC packs, obviously the ordinary model packs can be used out of the box in B3d
Actually the license of many of TGC's model packs prevents you using them in B3D. They have to be converted to another format for Blitz to load them and the license does not permit you to chage the format. I posted the contents of an email I received from them a year or two ago confirming as much.