I have all four colors because I really like Rilakkuma and figured I could use all the colors.

Each palette has a nice set of colors that go well together. I have used them without an eyeshadow primer and they are just fine alone and I have used them with a primer. The colors are more easily seen with a primer but sometimes it's nice to have more natural eye makeup and that's what these are good for I think. My favorite ones are the first and the third palette. The first one is coraly and the third one is pink based, they both have a decent mix of matte shimmer and glittery tones in order to create nice subtle sparkly eyes.