Me I'd be spending £100 extra safe in the knowledge you won't have any issues with whip or resonance. Match it to drives linked below and you'll have a very stable system capable of decent cutting speeds.

These Digital drives are the ones you want they knock the spots off those cheap CW-8060 analogue drives which can't compare in performance.
Leadshine AM882 Digital Stepper Drive 80VDC 0.1A - 8.2A With Protection Function | eBay

If you really want the best in performance and accuracy from a stepper/drive combo and can run to it then these are the ultimate.
Leadshine 300W 3-phase Hybrid Servo Drives Set HBS86H Drive + 86HS40-EC Motor | eBay