In my recent purge, I've noticed a major problem with a good 25% of my CND polish bottles. They are leaky, seriously leaky. This allows a great deal of air into the bottle, and volatiles out.
The result is that tightly closed bottles of polish are drying out, and stinking up my house (my SO kept complaining, and I could not find the loose bottle cap ... turns out that was not the problem).
Needless to say, while I love CND's Colour and Effects lines (the combinations are amazing!) as well as their awesomely quick dry time (out and about in an hour!) AND longevity (manicures lasting for a week!) ... I'm not buying any more CND polishes.
And another savings to my wallet! I'm practically down to China Glaze, Color Club, and Misa as my only polish purchases.
Ah, it is just as well, CND rarely bring out anything new and interesting, having spent most of their time on the Shellac line ... which I strongly urge people against due to the UV light exposure for curing. UV light is dangerous, whether on your body as a whole or your hands as a part. The lighter your skin, the more you should run away. I don't care how long it lasts or how great it looks ... because skin cancer is not worth the pretty or the longevity.