Standard size punches: 0.6 mm diameter
Advantages:
- less damage to the donor block
- more samples from any given donor
- more samples in any given recipient block
- easiest to remove the cores from the donor blocks
- easiest to remove the blank cores from the recipient block
Custom-size punches: 1.0, 1.5 and 2.0 mm diameter
Advantages:
- More robust, harder to damage (e.g., during training)
- Larger individual sample size
Potential Disadvantages:
- A tiny fraction of users have reported blocks broken by the larger punches.
- A larger but still small fraction of users have reported difficulty in removing cores from blocks when using the larger punches.