I like my bridgeport with the Boss 10 controller. How ever I'd question how great (or fast) it could to all out 3d contouring since the older controllers don't really do any look ahead thus they jump from point to point (accelerate decelerate stop, Ect.. Thus it would be pretty slow (I think) with multiple small point to point moves.
That said it is a great platform to start with. I figured I would swap my guts out for a mach 3 setup but have not as I like it to much so far.
DNC isn't to hard after you get the hand of it. Some weird quirks but probably different querks then my boss 10. I have not run any really long programs but I've had it quit on me DNC'ing in the middle of some programs at the same point which I can not explain why and had not had the time to figure out why.
Great platform to start with and less work over all if you gutted for a conversion then starting with a manual mill. Thats 1 great thing for sure.
Plus you can often pick them up for less then their manual equivlant because people "think they are trouble? but they aren't in mybook..