Recommendation for motors and controller with rotating nut

[JAZZCNC]

But how do they compare to those steppers Dean recommended?
Because they are cheaper and also use 220V AC...

They don't compare really, Servo's and Steppers can't be compared because they work so very differently.
However, as it happens I have those same Servos on my plasma machine and I wouldn't recommend them for a slaved axis machine because they are a nightmare to sync up.

They work nicely and are smooth and powerful enough for their size with 3000rpm but they wouldn't match those 10Nm Lichuan steppers in terms of torque where it matters, which is cutting. Also, they are much much harder to set up compared to the Closed-loop Stepper, which is pretty much plug-n-play.

If you are going to go for Servo's then buy better quality, like Yaskawa, Mitsubishi, Panasonic, or Delta they are more money buy but better supported. The Chinese servos are nice and cheap and quite good in some ways considering the cheap price but not very well supported or intuitive regards setup, so for the experienced builders only who are prepared to spend hours tweaking and tuning them.

The closed-loop stepper system is simple and just gets the job done, no fuss, no drama, the downside is they are a little slower and not quite as smooth as servos. But if you are only chasing 10-15Mtr/Min they work perfectly fine and will do everything the same machine fitted with Servo's would.

So save yourself the headache of using servos is my advice and stick with Closed-loop steppers.

Edit: Actually just noticed these are Lichuan Servo's which are not the same as mine, which came from BST (Fred) but still most of what I wrote above applies the same.