New Yaskawa servos seem to be about two to three times the price of Delta servos.

Delta servos seem to be 1.5 to 2 times the price of the generic Chinese (e.g. BST).

I am considering 750w Delta servos for a new mill build. Possibly the newer B3 drives, a bit more expensive but look to have good features. I am encouraged by the manual in comprehensible English.