I'd go for quality. Speed always degrades quality simple becaus eit increases vibrations and also holding constant pressure gets harder with higher speeds. The big difference is how fast quality degenerates with increasing speed. Also having 32 bit board is good, becaus eit allows petter compensation with nonlinear acceleration. But it also depends on what your target is for the printer. For mass production speed is more important than for home use where you just want to print something every now and then and you can increase quality and come away with a cheaper model that has good quality at "low" speed.