You can overfeed and overwater ProMix HP way easier than Coco. It holds both water and nutrients a lot better than coco or coco/perlite.
Also, not all coco are the same coco
I have used a lot of brands and by far the best brand there is would be Mother Earth IN MY PERSONAL OPINION. I'm running TheBucketCompany coco right now and it has horrible nutrient retention and drains way too freely and dries out way too fast. Not sure if its a higher coir fiber ratio or what. I know with Mother Earth I don't have as much PPMs in my runoff and it requires more water to get runoff compared to the bucket company's coco.
I have also used Canna coco, Fox Farms locococo and Royal Gold Tupur (not exactly coco) but mostly so..
Of all these brands and products definitely ME coco+perlite is the best.