Dear ;
I said before that the using of a special pole for Neutral is depending on the used Earthing System in your software house, as in some Earthing system the Neutral should be Switched-On & Off with the phases poles, so, the advantages and disadvantages are for the Earthing system and not for the Neutral pole. For exp. if you used ” TN-C ” you can't never use the 4th pole whatever the advantages.
In your case, it will be better to ask any Electrical Engineer in your place about the used Earthing system, then will decide if you should use the 4th pole in the circuit breaker.