Eddie, I think you have it right when you say, "I am not in the Machine shop business",
and I believe you need to ask yourself if you want to be. Either machine will get your foot in the door, but as a first step, consider if being a machine shop is really what you want to do with your life. The initial cost of the machine is only one factor. After adding rigging, tool holders, vices, perishable tooling, a computer, CAD/CAM software, insurance....add more for an air compressor, a saw, inspection equipment….. and soon you are a machine shop and not a designer and builder of UVAs.
I'm not trying to dissuade you from your purchase to the contrary; machine shop is a nice trade. What I am saying is that regardless of which machine, it is a big expense and requires a lot of time and skill to master. Unless you are careful, you can find yourself tied to a trade which was intended as a minor aspect of your business.
If you decide to move forward, the 3016 would be my choice. Unless things have changed, the 3016 was built on the same iron as the 4020, but with a smaller table and sheet-metal.  |