What do I do for water? Depends on which rig and where I'm headed. I use the 4 gallon Reliance in the van. While he van has a 12g water tank, I never use it so I don't have to waste time sanitizing it before each trip and the Reliance fits in the sink while underway. I take a Scepter military 5 gallon with a Scepter spout in the LX. I can get deeper with the LX and if something happened, I'd like a bit of extra water.
In the van, I end up purchasing a little extra water as needed because I might be gone for a week and am always passing through towns. I don't drink this water, I take drinking water separately. This water is for showers and clean-up (and teeth brushing). Same with the LX but I take that rig only when headed into back country. I'll usually carry a case of Costco water bottles in either rig for drinking, coffee making and food prep.