Tupperdors are fine. Yes, you have to wash it first to get rid of the plastic smell. You have to do the same with a cooler or wineador as well.
Keep your cigars at whatever RH works best for you. There is no universal correct answer. You'll find your personal sweet spot as you go along in this hobby. Don't stress about it, that's part of the fun. If you find you like them at 72, great, go with it. The only thing to worry about at that high of humidity is watching the temperature. High humidity and temperature close to 70 can be condusive to mold and beetle problems.