I charge 100% if I know im going for a long drive. so i get 500km instead of like 420. That is really no big deal. Since there are so many superchargers, charging to 100 is useless to me. About discharging to under 20, I am not aware Teslas have that issue.

There have been people that only supercharge and they do not show any problems that people expected.

I bought a large battery AWD tesla to deal with the winter. The range loss doesn't concern me at all.

This is with the old tesla batteries. The new ones are much better and will blow people away.