Studies have shown that homes where the bath tub that is not filled with water, stay ring free. Apparently they still used the bath, but only for taking showers. As far as the plastics go, it only takes one helping hand to come along once and clean the tub with the wrong cleaner to ruin it. Someone who is visiting and feels that they should help out, so they clean the tub for you. Other things like dropping finger nail polish remover will put a big blemish in it. But maybe the chances of that happening over a 5 years period are zero. The good thing about plastic tubs are that the hot water will stay hot longer in it. I personally can,t soak myself in a tub that is not all shined up. I feel that germs cannot live in shiny objects. I have never seen any home paint be as good as the factory baked on stuff. In fact, I have never seen a do it yourself kit for any project to be as good as what they did at the factory. My ideal bathroom would be seamless, no corners, nothing dark or dark shadows, all surfaces glossy, and cool white, and no busy designs like marble or such, a slopping floor with a drain. If you can bring in a fire hose for a good rinse, if it looks clean and dry when done, perfect.