Build time doesn't bother me as much right now as a number of things would make great masters to have produced in resin or die-cast for detail parts. Bill Denton's passenger cars are turning out amazingly well for DIY resin casting.
What is more of an issue right now than even the build times is the cost of consumables. This should improve quite a bit, but if it costs $20-30 per shell right now, you won't want to 3D print a whole consist.
-jamie
