I've tried many many low-poos.

This was what I've learned. The CJ Gentle Cleansing Shampoo was by far the mildest low-poo I've ever tried. It really beats the drugstore ones. No drugstore low-poo comes close. I wonder about the Jessicurl low-poo as well. I have a feeling that the higher end, curly low-poos are much better than the drugstore ones.

As far as other lowpoos:

The SheaMoisture poos are gentle as well, but not fit for low-porosity IMO. I preferred the Coconut-Hibiscus poo over the Moisture Retention poo, which built up on me in one use.

I've liked the Giovanni low-poos a lot, but not as much as CJ Gentle Cleansing in soft water. I've found in hard water, I liked them much more than the CJ low-poo. So water hardness makes a difference and I need something stronger in hard water. I must say that I don't feel a huge difference between the ones that come in the white bottles: Tea Tree Triple Treat, 50:50 and Smooth as Silk. I'd normally go for the latter two between those. However, I do like the Brazilian Keratin and Argan Oil one. I think it's a bit milder than the white bottle ones. If I were living in the Netherlands with limited access, this is the one I would pick:

Giovanni, 2chic, Ultra-Sleek Shampoo, Brazilian Keratin & Argan Oil, 8.5 fl oz (250 ml) - iHerb.com

These are the ingredients:
Aqua (purified water), sodium cocoamphoacetate, decyl glucoside, sodium lauroyl sarcosinate, cocamidopropyl betaine, simmondsia chinensis (jojoba) seed oil, panthenol (pro-vitamin B-5), beta carotene, guar hydroxypropyltrimonium chloride, *argania spinosa (argan) kernel oil, hydrolyzed paullinia cupana (Brazilian cocoa) keratin extract [phyto-keratin], *aloe barbadensis (aloe vera) leaf juice, *aspalathus linearis (rooibos tea) extract, *cocos nucifera (coconut) oil, *macadamia ternifolia (macadamia) seed extract, *butyrospermum parkii (shea butter) extract, sodium benzoate, citric acid, potassium sorbate, polysorbate 20, glycol distearate, sodium PCA, phenoxyethanol, natural fragrance

The bonus is it has some keratin. It's also much much cheaper than CJ's.
Alternately I'd use 50:50 for something more clarifying.

Other honorable mentions are YesToCucumbers shampoo which is fairly mild but something bugs me about it. I also don't really like the smell.

Original Sprout shampoo https://www.originalsprout.com/natural-shampoo

The BROO IPA one was definitely interesting. Not harsh but I think it left a bit of buildup so not fit for low-porosity hair.

Hope this helps.
2bc/ f / ii. low porosity roots + normal-high porosity shaft where bleached. normal elasticity.

Currently using:
Poo: Earthbath Oatmeal & Aloe
RO: V05 Kiwi Lime
LI: CJ Smoothing Lotion
Styler: UFD CM, CJ PP
PT: CJ Repair Me

hydrolized protein, jelly stylers
guar hydroxypropyltrimonium chloride, sulfates, jojoba oil
Neutral on cones.

iherb discount code: CFN646