Best hammer micromotor

Hi all, just asking this question for a jeweller friend of mine who
is not into computers. He wants to buy a micromotor that is made for
a hammer handpiece, he needs a variable speed one with good torque
and control, he needs to use it on heavy bezel settings.

I have suggested the foredom hammer micromotor but I know there are
other brands out there so if you could share your experiences with
your favourite hammer handpiece system that would be most helpful.
Also any pitfalls and what to stay away from.

I think he already has a flexible shaft hammer set up but wants to
get a good micromotor set up, maybe one that takes both hammer as
well as normal rotary hanpiece.

Is the hammer action all in the handpiece and would the control box
be the same for both.???

Thank you
Christine in the Ridge,