High concentrations of Peroxide will do nothing for you skin except dry it out severely. As a cleanser a 5% BP will have the same cleaning effects as a 10% BP. There's only so much that can be cleaned and 5% takes care of most of it if not all.
hydrogen peroxide is not the same thing as benzoil peroxide. The hydrogen peroxide solution you buy in the store is 3% hydrogen peroxide and is fine to dab onto your skin or even use as a toner. It is an antibiotic and will "fizz away" the bacteria, blood if there is any, or damaged tissue. It may be sore or irritated or red but that passes shortly.
hydrogen peroxide is sometimes reccomended as a toner, but Paula Begoun (the "cosmetics cop") said something about letting oxygen into your pores and messing them up...i don't know, she said don't do it lol. the only time i use this on my face is after i pop a pimple and its bleeding, then i just put a cotton ball with hydrogen peroxide on it for a while.
I wouldn't do it. Paula Begoun started out recommending Hydrogen Peroxide as a toner, so I treid it, It ruined my face!!! Then She came out saying that after more research, you shouldn't use it! She states that hydrogen peroxide releases unstable oxygen molecules on to the skin that generate free radical damage.