i was an avid 10% user for years, afraid that 5% or 2.5% would no way no how be as effective. When I did switch, as an experiment, I found that 2.5% really is as effective, and far less irritating. I think 10% even if it doesn't make you dry overall, does cause some flakiness which is a big no-no. If your skin is flaky and brittle on the top layer, it can actually help clog pores, and trap the bad stuff in there. I always thought i had sensitive skin, but when i got off 10% and started using 2.5%, i realized my skin wasn't nearly as sensitive as I thought. I think Scouse's suggestion is a good one.