Samualt,
All I can say is that a mill would be more rigid than a router (especially when you consider machining metal). On the other stuff i'm not going to make statements of things i don't know much about. You can consider BobCad however as programming software, but there are other software also to consider..... Guys like Rekd, Huflungdung, CadCAM, Woodknack,WMS, CAMmando etc knows alot more than me on this specific topic and would be glad to answer all your queries.
Klox