I use the 20% Skin Refinish alone. So far, I love this stuff. I've only been using it for about two weeks (and normally I'd wait longer to review a product) but this stuff is so good, I just had to share the good news with fellow acne sufferers.
With M2 Skincare (formerly Mama Lotion) you get a LARGE 50 mL, 20% mandelic acid bottle for $25, instead of the TINY .25 or 1 mL, 10-15% mandelic acid bottles sold on GoW or Diana Yvonne for upwards of $40. GREAT VALUE, especially by comparison.
The burning feeling lets you know it's working and YES, you can wear it under make-up with or without sunblock/moisturizer.
CANNOT RECOMMEND THIS ENOUGH!!!
I am Jamaican and thus get hyperpigmented brown marks from any place I've had a cyst, whether or not I pick them. Additionally, I had to get rid of gram negative folliculitis (inflammed acne-like tiny bumps which are resistant to everything, caused by prolonged use of antibiotics), which not only raped and pillaged my forehead but then spread to the sides of my face, nose and cheeks too. (For that I took Bactrim 2x daily, began seeing a Chinese herbalist and soaked my skin in vinegar at least 2x daily which really worked but left dry, darkened, almost scaly skin..and then began mandelic acid after a month to get rid of the "scaly skin" and now my forehead skin GLOWS its so soft and smooth.)
M2 has left my skin soft, supple, smooth and literally almost PIMPLE FREE in a matter of a WEEK. Thus far, it's AMAZING and works BETTER than Tazorac. I'm definitely sticking with this brand if this continues! My acne WAS moderately severe but since I've stopped eating ALL dairy and began using "Mama Lotion", my skin has two grain of salt sized pimples and one small cyst which is shrinking.