I would choose carefully when buying a duplicator. Rigidity, balance and weight are your friends here especially when doing the inletting portion for the action and barrel to avoid gaps. Almost any good quality router motor or spindle will provide enough power to cut with but you really need the weight and control to do the fine work required to do a good job of finishing and save yourself a ton of work on the backside of your duplicated stock. I've heard pretty good things about the Dakota duplicator if you can get your hands on one, but the Gemini is borderline for rigid and I'd avoid the Radar alltogether. You can get it done with the Gemini but it will take a little longer than a better grade of machine so I guess it depends on if you want to make it pay for itself or you just want to use it for hobby stock duplicating.