Comments about Marykate MaryKate Nu-Teak Cleaner:
I've used several different teak cleaning products and this one is the best. It's easy to use, cleans the blackest stains, and doesn't ruin the grain. I followed up with a teak brightener (or just use a bleach solution) before oiling the wood. My only regret (and the reason for four/five stars) is that it is a harsh chemical and can sting if you get it on your skin.