#2 should be adequate with your current load. If you were going to add a large inverter, then larger wire would be required.
Others opinion on the smaller disconnects are not accurate. Pianotune is correct as to rating. Many people try to switch while under heavy load. This causes arcing on contacts and causes early failure. This can happen on many types of switches. Very large loads such as inverters need to be turned off if they are routed through a disconnect switch. My opinion is these should not go through a disconnect.