Just finished trip to Virginia motorsports park 4 days dry camping with sons family of 4. No problem with showers for 6 of us and tankless hot water ,shower miser saved a LOT of water especially gray tank volume . Don't think we could have done this without it. I also used sewer caps with garden hose connection on both sewer outlets and female to female connector and my orange garden hose to tie my 2 gray tanks together,that gives me 80 gallons of gray capacity.