Our camper does not have a battery disconnect. And I have never had occasion to want one. When do you use yours? (And don't say "When you want to disconnect the battery.")
The battery disconnect in my Bigfoot will turn off everything, including the smoke detector and CO detector. The object of this device is to prevent idle time battery drain when the camper is not being used. Having those parasitic draws bypass the disconnect makes it useless. In m opinion the disconnect should be between the battery and everything else.