Oh, my "mill" is actually a mini-mill. Technically it is a CNC router, and it's good for all of those operations. Mine is "huge" for a mini-mill because it's got an 18x24x3 inch working area. But the spindle is actually a trim router. Between being decently accurate and colletted for standard end mills, I'm not too upset about calling it a mill.
The difference between a mini-mill and a regular CNC router is that a mini-mill is built with a more solid frame for better precision. The router as a spindle is the weakness of the design of course. So I usually get ~ 3/1000 accuracy, but if I mess up, the bearings go aggly and then my precision goes to hell until I replace the router. The good news is swapping in a spare router is easy and takes 5 minutes. The bad news is messing up happens way too easily when working in steel, which is why I make the switch plates out of brass or aluminum. It can handle 1/8 inch steel for the switch plates, but for that I have to be careful. For steel any thicker than that, even the slightest mistakes can mean I have to replace the spindle again. Accidentally using one slightly dulled end mill --> replacing one busted spindle. Know your limitations and all that.
Aside from a weak spindle with weak bearings, the difference between a mini-mill and a regular CNC mill is that the mini-mill weighs under 200 pounds. This means I can carry it up and down stairs by hand, load and unload it out of vehicles, move it in regular elevators and without a fork lift, do custom while-u-wait work for walk-up customers at shows, use running operations as a crowd draw, etc.
I've never had any problem with cutting plastic on it, although if I'm doing a production run of more than a few dozen of something I usually cut an injection mold instead.