I have a project on the go that would require a TCer or van to be built specifically for this project. I have also considered the hot water issue as this unit will not have a huge water tank rather a couple of the large portable water jugs that the pump will draw out of.
My decision is that I will still have a hot water tank. As mentioned above it is so nice to turn on the tap and get hot water to wash up or to wash dishes or, or. For the minor cost of the hot water compared to no hot water in a new TCer I think it is worth it. Plus waking up on a crisp or cold morning to be able to wash your face in hot water is sooooooo nice.