I have just received a 3D printed schoolbus bodyshell from I-materialise. This is in their grey prime material, which is not available from Shapeways, and far superior to anything Shapeways offer. Four photos here show the fine detail of the print. Very fine printing lines are visible, but these are smooth enough to be negligible, and the big difference between the grey prime material and the old WSF, is that grey prime can be cut and sanded with ease. It is a resin based material, similar to resin kits, whereas the WSF material from Shapeways was a hard nylon based plastic, that could not be sanded or smoothed. The grey prime is not as porous as WSF, and so should be far easier to paint. I will report when I have tried mine.
And now the bad news. You get what you pay for. This print worked out about €25 or €30 dearer than the equivalent Shapeways print in WSF. That means that at best, these models would retail 60%-75% dearer, or more, than Shapeways. The short wheelbase SS schoolbus would work out at over €80. That is very damned expensive. But the quality is much better. Typically, the more common bus types will continue to be made available as resin kits, and this 3D printed medium will be the reserve of more exclusive, one-off types, that would not merit a minimum run of 50 resin castings.
It may be possible to reduce the cost somewhat, by reducing the shipping costs on bulk orders, and possibly by offering a 'bodyshell only' offer, with floors, wheels and seats at the modeller's own discretion. At this point I am open to any and all comments on this. What would modellers be looking for, based on the apparent pricing costs of 3D printing, and the quality issues with the cheaper materials? I may continue to make the models available in WSF through Shapeways, but I cannot give any guarantees about what you will get from them. Individual quality of prints varies widely, and Shapeways appear quite content for quality to be a lottery, depending on who prints your model. This grey prime material from I-materialise appears to be far better quality, but you pay for it, unfortunately.