The combination Drum/Rotor machine is a good unit. Most of the shops I worked at had those and we used to cut all drums and rotors as standard part of the brake job as long as it was possible. Later shop had a STAR machine. Same basic idea, but much heavier casting and electric power feeds instead of mechanical.
All the AMMCO lathe hardware we used on the combination and rotor only machines was interchangeable (1" arbor?). There is a smaller diameter arbor also available for really tiny stuff like older import drums/rotors and that adapter tooling is independent of the normal tooling. I think there was a large scale machine too for class 7/class 8 category brake stuff too, but you would know it, it would be very large in comparison.
Make sure all the power feeds work correctly, both speeds on the rotors and the variable feed on the drum side. More adapters = better. Get as many as you can for both hubless, composite and bearing types. Silencer bands are a must, but you can buy those new easily, as they do deteriorate. I found the pucks to be about useless, myself. The original DOE wrench is a nice touch, but by no means necessary.
If I had the room (and everything here didn't rust out so badly), I would have one too.
you can usually get one turn out of them