Our program has been using the Probotix's Meteor
http://www.probotix.com/METEOR-CNC-ROUTER?search=meteor
I also have one of the
http://www.probotix.com/V90-MK2 at one of our middle schools.
We have used the Meteor machine for two years now. We use it for aluminum sheet and stock up to 1/2" as well as all kinds of plastic.
The machine comes assembled in the crate. They offer some options on the router that you provide yourself on the larger machines.
We purchased collets from
http://www.precisebits.com/
Both companies are great to work with.
Let me know if you have any questions.