Review (5/5): Love it!
As a WOC with black hair, the Dark Brown is perfect for me. I use it once a week or so, but I'm not really one to upkeep so its more like once every two weeks. I do sometimes leave it on longer than the package says and I haven't experienced any irritation.
I also divide the capsules in smaller portions because the capsule has sooo much product. I usually open a capsule or two and keep the product in one of the little empty plastic pots for lip balm. I bought a 3 pack from target for $1. Walmart may also have them.