Ridiculous comment about it being expensive - total bollocks.
I'm about a year in to using it and it has transformed my skin.
They are amazingly helpful - if you email them with what you want to fix, they tell you what you need.
The point about all the many individual elements is that you can tailor it specially for your skin. So, you can select four or five different actives to use in combination to get the best results.
And those five individual ones will still cost less than one serum from Clarins or similar, which will have the same range of actives, but at lower potency.
It's not perfect - there seems to be a cost of understanding as a barrier to entry. And most, but not all, of the criticism here seems to be that people don't understand the point of it or how to use it.
And I thought the Caffeine eye serum was appalling and it went in the bin, although I see others upthread liked it.
On foundation, they colour match for you - so I told them the exact Estée Lauder shade I use and sent a pic of my skin in daylight, and I've received today two samples to try to see. Looking forward to trying them tomorrow!
At the moment, I have probably eight different potions on the go, which I use in specific combinations and orders morning and night.
I should say as well - I have nothing to do with them! But I take skin care seriously, researched it and spoke to them a lot, and built up a range of different elements that work for my skin, over time.
And the investment has well paid off.