There are alot of good grain mills out there. I have one of the less expensive ones, a phil mill I, and have been perfectly happy with it. Mine is only a single roller mill, if I had it to do over again I would probably get a double roller mill. Some things to think about is how easy is it to adjust the gap setting for different malts? Can you hook up a drill or motor to your mill? And of course price. I think for my money I would go with a Crank and Stein mill. They have a package deal that comes with a double roller mill, base, hopper and drill attachment for about $130. A friend that I brew with recently got this same package and it is nice. Check out there site
http://www.crankandstein.com/
Hope this helps.
Doug