When perusing e-Bay on the day that I purchased China Glaze Custom Kicks, I did my customary Google search of "Name of polish + dupes" in case I was going to all this trouble for a colour that I technically already had.
The search came up with The Real Teal, a colour that was much more readily available in stores and would cost about half the price. I also already owned that colour, so I became hesitant about buying Custom Kicks. Another blogger mentioned that the only difference was the colour of the shimmer. I agonized for days, until I decided that different coloured shimmer, especially GOLD SHIMMER, was enough of an excuse for me to own both.
For about a year, I was convinced that I had two of the same polish in my collection. On further inspection, they are even less alike than I had originally expected. The shimmer in Custom Kicks is much more subtle, almost appearing to be a creme. The Real Teal is more packed with shimmer, teetering on the edge of frosty when compared with Custom Kicks.
The shimmer is a different colour in both, gold for Custom Kicks, and green/teal for The Real Teal. However, I think that the difference in the overall colour is more notable. Custom Kicks is a tad lighter and bluer than The Real Teal, which is unmistakably...teal. For real.
Do you need to own both? I would not call them dupes of each other, but you probably don't need to own both unless you're a die-hard teal lover like myself. Only fellow polish addicts will tell you they are different, I'm sure.