I started with a Shapeoko 2, but those plastic wheels are worthless. I decided to make my own that is capable of anything I can throw at it. This one uses misumi extrusions. Guys if you are struggling with getting the t-channel nuts to line up, get a nut rail. I got this for attaching the Hiwin guideways and it was magical. The nut rail can be custom made with a spacing that you specify.
https://www.youtube.com/watch?v=KfcmfX-xigI