If you want to engrave in 3D, get your wallet out. None of the inexpensive 3D CAM packages will do it.
If you want a simple, easy to use 2D CAM package, Cut2D is what you want. Should be about as close to bug free as you'll find, as well. All Vectric products set the bar for ease of use, have awesome support, and just plain work. SheetCAM is good as well, but I haven't seen it in a long time, so really can't comment on it.