3D models don't have to be recreated in 2D, but they do have to be oriented to eliminate undercuts, and often broken up into more than one piece to reach everything. I use the code that TCC produces as a start, and I learned enough about manual coding and editing to introduce z-axis strategies. My own homebuilt router/miller has a fourth axis that isn't powered, but has a y-axis 90 degree index, so I run one file, reorient the model about the datum axis, then generate more code. I can deal with many undercuts that way. Toolpaths generated by TCC are 2/2.5D, but judicious manual editing goes a long way. TCC's visual feedback of an edited code file shows me what I've done to the toolpaths relative to my model, which gives me more confidence. At the time I bought it, there was nothing with the same sort of CAD capability integrated with CAM at the price level. I bought TCC 2 back in the days of TC V10, and subsequently TCC3, which I haven't had the need to go beyond. I'm a drafter/modeler, not a machinist, but I was able to amortise the investment in program and machinery quickly, machining prototypes and casting masters. I learned a lot and got more capability at no cost, in other words. Professional machinists probably have more sophisticated needs than me, but for this amateur, it was a good buy.