Good. I wouldn't say the colour adapts perfectly, it's not bad. the medium is too dark (i had a sample) and the fair is just a bit too light but i can work with it (put bronzer on). It is definitely convenient as you can reapply instead of taking make up off and on, so on holiday, on the go etc, the protection is supposed to be good so I'm pleased with it but it's not Wow'ed me so I will still be trying other products from other brands
I absolutely love the Colorescience Flex and how wonderful it makes my face look and feel. Too early to comment on its efficacy. The brush on sunscreen is tricky to get flowing and you have to bash it upside down really hard to get it flowing and then quite a lot comes out.