After some extensive tests, they do work nicely, and they are reliable for sure (the boards).
I still have no idea how much they cost.
Pros:
Nice and easy to setup and use, nice form factor, no need for separate power supply for the RPI3, separate connectors for easy wiring, stepper controller has built in 4 places for motor drives so you get a very compact complete controller, can output clean pulses at over 900 kHz as verified by the scope, servo controller has 1 analog input with adjustable sensitivity (up to 200V i think ).
Cons:
RPI3 is to slow, but very usable for use as a cnc controller, meaning when used as a cnc controller it is absolutely usable, but for preparing things for machining ( CAM ) should be done on another computer. Also an update of the rasbpian distro and switching to software rendering improved the usability of Machinekit by a very large margin, from meeehhh usable to absolutely usable.
All in all, very nice and very usable for what they are, a small size easy to setup and use controller for small cnc machines. I really like the stepper one, mount an RPI, add 4 drives, connect 2 power wires, connect motor wires as needed, USE the machine. It is by far the easiest CNC controller to wire.
There are add on cards with more IO, can be used together for more axis, etc etc.
Regards, need sleep it is 3:32AM here.
