There are quite a number of electric tankless or mini-tank systems being sold at Lowe’s, Home Depot and the like, so it’s not as if they’re somehow novel or questionable. Gas is much more common but I know people who have them and are happy with them. As far as mineral deposits, I as well as most people I know on well water have issues in that regard and have whole house water filtration and softening systems, those are not that costly either and come with new construction now. The water is acidic here, not doing so would put pinholes in copper plumbing eventually and wreck the house with water leaks all over the place.
[There are quite a number of electric tankless or mini-tank systems being sold at Lowe’s, Home Depot and the like, so it’s not as if they’re somehow novel or questionable.]
Didn’t say they were.
In my experience they can be problematic and I typically don’t recommend them to customers in my area. The new tank type heaters are extremely well insulated now and supply copious amounts of all the hot water you could need ready to go. Even with multiple simultaneous fixture draws.
Anywhere there is an extreme temperature change you will build mineral deposits. Even with softening systems depending on how good they are running. Tankless are much more susceptible to that due to temp difference. Not every homeowner is into acid flushing their tankless on a regular basis.