I own shades 10, 6, 7 and 15. The quality of the product seems to vary between shades. Based on my own personal experience, the more vibrant colours tend to apply better/ more evenly, last longer, and leave strong stains. I have heard shades such as #18 & 19 leave very little stain and apply quite unevenly.
#10 was my first purchase, a beautiful red, which my mom fell in love, so I gave to her. After being applied, it turns a lot redder than it appears in the tube, so be aware. Then I purchased #7 - a beautiful peach coral, which in my opinion is the most natural shade in the range. I bought both of these 2 shades at David Johns in Sydney, Australia. They are retailed for $50 each, which is a complete rip off.
I then purchased #7 and #15 online for about $37 each. I thought I would have loved #15, being a medium pink, but to my surprise, I was quite bored with that colour. Instead, I was completely head over heel in love with #6, an orange shade without strong red undertone. It really brings out the colour of my nc15-20 Asian skin tone, gives me a vibrant and lively look. I used to love it much more than Revlon Lip Butter #15 Tutti Fruitti, another orange shade but with much stronger red undertone.
The product itself is wonderful, judging from the 4 shades that I own. I would have loved them more if not for what they had done to my lips. I knew all lip stains are all quite drying, but after wearing them pretty much non-stop for 2 weeks, my once healthy lips have suffered. They are now tender, red and dry, despite me using paw paw oinments on them every night from the very first time I started wearing them. The product contains high level of alcohol. I have very sensitive skin, and I've always been careful about avoiding products with alcohol. I blame myself for not checking the ingredient list.
I'm very much saddened by my experience. If you have sensitive skin, please wear them with caution.
#6 introduced me to the beauty of orange lip colour. I've purchased MAC Saigon Summer about 2 days ago. I hope it will be able to replace #6 for me.