I only used this product because it came with the eyeshadow palette when I bought it, but I do not think it is necessary to have. People told me your eyeshadow will only stay on if you use their primers, but it has always stayed on for me.
I bought a product similar to this one. I believe it was only a 10 piece set. I loves the square shape of them, but I hated that they came in such odd sizes. I never really used the small containers as I would’ve rather used my money elsewhere and bought a different set.