[member=32478]mcooley[/member]
My personal experience is limited to buying a early kit on inventables, partly assembling it and then selling it because I decided to go another route. With that said I have a fair bit of second hand experience and information, and much that is relevant to the early machines is changed now.
Edward Ford has been involved since day 1, he used Makerslide extrusions (originally a Bart Dring Kickstarter project) for the original mill (i.e. Shapeoko 1). Later he had some arrangement where he was an employee of inventables and made modifications and improvements to what became the Shapeoko 2. I think last year he parted ways with them and joined up with the Carbide3D guys and did a total redesign for V.3.
Bottom line on all that is the V.3 is totally different than V.1/2, so a lot of what you may read about those machines is not applicable to the V.3. Instead of using Makerslide they now have a custom extrusion that looks much beefier. They also made their own controller card instead of using an Arduino with a grblshield, although the core firmware program processing the g-code is still grbl. Also the early versions used NEMA 17's and the newer ones are NEMA 23's, more power and torque. Carbide3D also created their own g-code sender in lieu of one of the open source ones, and are working on their own CAD/CAM software.
My personal opinion is that the V.3 is a lot of machine for the money. The inventables version of the machine morphed into the X-Carve (also around $1,000) and Peter P. did a review on it elsewhere on the FOG. The $1,000 X-Carve has a larger working area but I think the Makerslide is being pushed to it's limit (the extrusion is only 20mm by 40mm) while the new Shapeoko extrusions are more substantial. If you are planning on cutting aluminum or harder materials the larger X-Carve could have some issues.
Full disclosure - I recently ordered the Carbide3D Nomad 883 myself, wanting a non-kit machine I could have in my office/work room and run inside the house. I probably won't receive it for a couple months, but just in time to fiddle with it during the depths of winter without tromping out to the shop.
Hope this helps.
RMW