I am the new guy here but I have had pop-up campers for many years with the A/C on the roof. I can promise you the condensation from the A/C will run off the roof at exactly where you don't want it (door, open window, etc.) The drip, drip, drip will get to you.
If on the boat it is channeled to the enclosed box along the shower water and water heater drain and then pumped overboard at the same place all the time then I will take it.
Patrick