There is a post over on the Practical Machinists site where this guy has put a set of servo's on an old BOSS Bridgeport.
Now on a machine this size I'll grant you they are better but many were made with steppers, you just have to keep within limits.

However he started in Feb 2012, it's on 14 pages so far and he still hasn't got it running even though he's thrown $$$ @ it.
Currently he's looking at some more new servo drives after having blown the other up.

A stepper machine would have been cutting with a month.