I tried Curl Keeper a couple months ago, and I have mixed feelings about it. For the record, I am mostly type 3b (some 3a), normal porosity, med/thick density. I used CK underneath my gel (so I put it on in between leave-in and gel). I bought it to get some extra frizz control, and I honestly didn't think it made a difference in my frizz. It did cause me to lose some volume also (I think it's the ingredient hydrocellulose that causes the volume loss). I personally like volume so I was sad to lose it, plus I was disappointed that my frizz seemed no different.

I've only tried it in the fall/winter months, so I am going to give it another try in summer when the dew point is higher. Many curlies swear by it in humid climates, so maybe it will show its value then. But in my limited experience, it really accomplished nothing for me.
My hair: 3b, corkicelli, medium porosity, medium texture, medium/thick density

Co-wash: DevaCurl NoPoo
Rinse-out: GVP Conditioning Balm
Leave-in: KCKT, Suave Naturals Coconut, or my rinse-out!
Gel: SS FHG (my new HG!!)... I also like HESMU, AIF, CJ CQ, BRHG, CJ PP and the occasional LALSG

Likes: Plopping!
Dislikes: Glycerin

CG and loving it!