The different water systems are really a toss-up type of deal for the average vintage trailer owner. For me, it was just another notch on my tool chest handle to take the onboard compressor and pressure switch apart, service, and replace. I also did some vibration isolation while I was after it. It's little tasks like this that keep me happy, happy, happy. :B
If I could have replaced the tank and pump for $160, I might have gone a different route, mainly for the weight savings. I replaced all the plumbing with Pex and new fittings so galvanic corrosion from dissimilar metals is not a worry.
I do have another mission in mind for the galvanized tank. I'm thinking about taking the diversionary load from my solar controller and powering a heating element in the tank. In winter, the elevated water temperature would act as a passive heater and the tank is under the dinette bench so it is in a prime location for that.
