Smilem: I would guess the main reason is that it's USD $40 for one controller board.
As for the chip on the board, the TMC260 is about USD 8.70 from Digikey, and won't fit in the usual standard Pololu form-factor.
That said, if this DICE form factor takes off, it should be possible to put it on one of those easily enough.
As for the chip on the board, the TMC260 is about USD 8.70 from Digikey, and won't fit in the usual standard Pololu form-factor.
That said, if this DICE form factor takes off, it should be possible to put it on one of those easily enough.