I changed out both elements in my electrc water back in late August. Had to change the bottom one out again today.
RO also puts about four times as much water down the drain as it filters. A whole house RO filter is extremely wasteful. You don’t need to be filtering every toilet flush.
Yeah, I think most people, myself included at one time, are more fascinated by RO than we understand the practical considerations.
Use RO locally at a single tap in the house, if the water quality warrants it. Perhaps add a desalination unit before the water heater, or centrally if you have some very hard water. But a central RO? Sounds expensive.
I’ve considered a central RO for prepping purposes, but even then a gravel/sand/active charcoal filter, followed by a UV-C mercury lamp, would probably be more cost effective, and easier to maintain without access to replacement membranes.