For 12 and 24 vdc systems (like used in overland vehicles) I would advise using either marine or solar type breakers instead of just a switch - this allows them to work automatically (perhaps) when a problem occurs - but, for the larger sizes (over 100 amps) it is possible that they would not trip... but that is why using a breaker is nice as you can access the handle on them and shut them off.
I've had a breaker panel in my sprinter for about 11 years now with a 250 amp breaker for my inverter, a 100 amp breaker for the connection to the vehicle alternator / battery (via an isolator relay), a 60 amp breaker for my solar and a 20 amp for my fridge. Need to still add a couple of more breakers for DC outlets - currently just using inline fuses. I've never had them trip off from vibration or shock - and I have driven many bad roads (even with bad shocks for a bit).
Look for them from companies like "airpax" or "carlingswitch" or "heinemann" and the best prices are probably on line from solar / inverter suppliers.