I have close to 100 OPIs and than less than 10 each in Orly, China Glaze, Zoya, Essie and sally hansen brand. I have 1 Chanel and 1 Dior. I LOVE Diors staying power but not the price..
I'm a huge fan of OPI polishes. I can wear it for about a week before it starts looking unpresentable. This is a huge feat in my opinion, because I work in an office and am typing on a computer a LOT. I can't begin to guess how many bottles of OPI that I own. My favorite polishes from OPI are the Designer Series, due to all the sparkle they have.
I love China Glaze and OPI the most, but the Sally Hansen Insta Dri line is also one of my favorites because the colors are all so pretty, opaque, and easy to apply IMO.