This is my approach of the SpaceX Coaster. 
It was a nightmare to glue the pieces perfectly in place so I made a Multicolor version of it.
I completely redraw it from scratch, as there were no stp files available. For now it is just a multicolor print, but I'll also release a version for single color printers which is much easier to assemble. 
All my coasters were printed on a MK4 with MMU3 in PETG without a flaw.