Thanks for the feedback guys. Been a bit busy.
So if I go through with learning this all now, I guess I am left wondering what I should do then for a CNC package. I have a manual Sherline, and in my budget I'm gonna basically have to do a homebrew NEMA/controller install as the 'factory CNC kit' is more than I paid for the machine. We're talking about a few hundred bucks vs 2 grand. The lathe already has NEMA motors installed but I don't have a controller. Best case scenario I can find a way to share controllers between the two; but that limits me to running one at a time (probably not a bad idea regardless)
I guess my hesitation is that for me to DIY this stuff, it could be months of tinkering with cheap hardware. So I'm gonna have to really start on it right now. I've spent months tinkering just to get the 'ready out of the box' Makerbot Replicator 2 into a reliable machine, which still seems to always go back to caddywhompus whenever I get new filament of course... so I can only imagine the puzzle that setting up a CNC controller could be.
I'm kinda leaning towards Mach3, anyone got experience for/against that?