How many hours a day do you figure you will run it? Will you have to run the main while it's running or will the batteries keep it going?
The solar panels and batteries will easily handle running this Katadyn. I anticipate running it several hours a day from ten a.m. until the tank is topped off. The first two hours will fill my 3 gallon solar shower so a long hot shower has been added to my list of wonderful things about life afloat.
I bought this one:
https://www.amazon.com/dp/B000J2Q0SU/
My plan is to run Katy to fill the shower bag then test the water/switch over to my water tank. That way the water in the solar shower will have all day to get toasty warm.
As for duration of run, the Katadyn 40E puts out 1.5 gallons per hour. I don't know how much water I will use once I don't have to haul it to the boat. More than now for certain!
To be able to take a long shower is a luxury. My hair is long and it normally takes a gallon to wash it and me. I look forward to longer hot/warm showers without a care in the world.
A watermaker though costly offers me the opportunity to anchor in remote areas and not worry about having enough water. Even in not-so-remote spots knowing I had to haul water to the boat meant I didn't drink as much as I should have.
I really dreaded hauling water. It's hard work.
The tank fill is on my bow so I had to come up to the boat, lift the water jugs up to chest height, tilt/not spill the water into the pipe and then do it again for the next jug/bottle. Ugh.
Maybe a fellow who is a foot taller would not have the same physical constraints however for me, it was not so much fun. On the other hand, even while standing on Algae's middle seat (to get the height right) I never fell overboard so that's a good thing.
I have pretty good balance. Knock teak!