Solidoodle 3 for $699 or Solidoodle 4 for $999?

[Mcbride19]

I'm not talking about the layers height resolution, quite all the printers can make 0,1 mm 0,2mm and 0,3 mm height(0,2mm is 200 micron and not 20 micron !)
I'm talking about the X/Y resolution not Z, it means how much precision the horizontal moves of the head have.
Of course the SD2(or 3) as many others can make layers that have 0,2 mm height and even 0,1 mm.
But it's horizontal resolution(X/Y moves) is 100 micron and the rostock max is 20 micron( I think it's because of the delta system).