Advice on motors for c-bot. (3 replies)

I wish to upgrade my Prusia I3.
I am considering making the C-Bot core-xy printer.

The BOM for this printer states the NEMA17 motors should be 68oz-in (48N-m) or better.

Looking at Ebay I can find these:

Manufacturer Part Number 17HS19-1684S1
Step Angle 1.8°
Step Accuracy 5%
Holding Torque 45Ncm(64oz.in)
Rated Current/phase 1.68A
Phase Resistance 1.65ohms
Voltage 2.8V
Inductance 2.8mH±20%(1KHz)
Weight 400g

.. and these:
Manufacturer Part Number 17HS19-2004S1
Step Angle 1.8°
Step Accuracy 5%
Holding Torque 59Ncm(83.6oz.in)
Rated Current/phase 2.0A
Phase Resistance 1.4ohms
Voltage 2.8V
Inductance 3.0mH±20%(1KHz)
Weight 400g


My questions are:
- Do I really need 68oz-in motors? Would I be better off using the 45N-Is thecm motors?
- If I went for the larger motors, would I encounter problems driving them with a Ramps1.4 and A4988 drivers? Would I gain anything by using DRV8825 drivers instead?
- Are there motors better suited to this application available (preferably in the UK) for a similar price (£9 each).

Thanks.