If you are looking for a high number of breakers the geist metered PDUs can support 6x 20 amp breakers for 2 miners each at 240V, so up to 12 miners per PDU.
If there is a problem that shuts off the breaker the PDU is attached to you will lose a large section of miners. Having a breaker trip and 4 miners shut off is much more desirable than losing 12 at once IMO and if you have a melted plug or something else that needs to be addressed there will be a ton of downtime.