These smaller jars are just perfect for trying out the different serums without buying the big jars - you only need a tiny bit of each serum and it can also act as both serum and moisturizer (for me anyway, with combo skin). You can also put more moisture or an occlusive on top (I just go straight to the Hydro Priming Cream before makeup). The Chundra Taga is my favorite so far, very plumping and lovely! They look like goop in the jar but melt into your skin just like a liquid serum, so only take a tiny amount to start. I love them and will keep using.