I've had both flushers, got the foot flush in the Escape cause I didn't like bending over for the low toilet in the Starcraft. Ended up a moot point as the toilet is raised in the Escape. It is a bit awkward to press the foot flush as it is raised along with the toilet, but not near as much as folks make it sound.
To keep the toilet valve open for cleaning the black tank, one can wedge something in on the upper handle or use a Johnny Chock https://www.amazon.com/Prime-Product.../dp/B000BGOJ32
. For the foot flush you can hold it with your hand or foot. I use a home made "T" that works like the Johnny Chock, even with the foot flush. it's just easier when dumping a pail of water down.
Don't know what others do, but after I dump and flush out the tanks I dump a pail of clean water into the black tank along with some Happy Camper deodorizer.
If I were to order another, I'd probably get the hand flush model but they both do the job.
As far as the water shut off goes, it doesn't hurt to have one and would sure help on the off chance your toilet starts to leak. Think of not having shutoffs on your home toilet, without it you'd have to use the main whole house shutoff. I added one after I had the trailer, you can also use it to adjust the water flow to the toilet,