But we do know how the protection system will work. It was stated by Fagex already.
It's gonna be the same keep 1 item system that'll be for your highest priced item, It also said over 500K at one point.. but that part has been removed since so I'm not sure if that's the case anymore.
My opinion on the best pray lvl for pures would be:
1 if you're lower than 60cmb without Ancient Spells
11 if you're lower than 60cmb with Ancient Spells
43 if you're higher than 60 cmb because of clawfags
52 is a waste of time, all it does it make people use their p pots faster and cry.