I will pipe in to say this - MO is a mixed bag. For some it's a god-send. For some it's a nightmare.
It seems properties play a big part here. Porous curlies tend to like it more often, and low porous curlies tend to have problems with it more often.
My hair is highly porous, and sealing with some MO has been an amazing solution for me. It's become an HG. I have no issues with build-up, but I do low-poo every now and then, as well. (However during times when I've gone strictly co-wash I never had any issues, either.)
I think a lot of it is in how you use it, and in amounts.
That being said - I would not try that product, either! Lol! Too pricey, and I already put MO in my hair, so I don't use it in products very much. (Though I've used the k-pak with no issues.)
2c/3a/3b, Fine/med, Dense, high porous, & normal elas.
Lo-poo - Renpure Keratin, SMR, Giovanni SaS
clarifying - mix Johnson's H2T with low poo
Co-wash - Suave Nats. clar. or coco.
RO - GVPCB, Ion Eff. Care, TN.
LI - SMR, Cure Care, or RO
Seal - MO or Jojoba
DT - + honey, ACV, & EVOO to SM masque & GVPCB
PT - Gelatin!, CNPF
Styling - FSG, AIF, BRHG, LALS/PS, GF curl spray gel, SM Souffle/Smoothie, LOOB
Oils - MO!, EVOO, jojoba, GSO, SM Elixer, EVCO, VO5 Hairdressing