Well, I’m a big fan of media like coco and Promix. The downside is more maintenance. The upside is faster growth.
I germinate in peroxide and water then right into a Solo cup of my chosen media. My current grow is in Promix HP and I just put the sprouts in that and run em out with distilled water until they are in veg then move them to a larger pot size and introduce nutrients. I never could get peat pots to work worth a darn and never tried rapid rooters or rock wool. I don’t have any trouble.
MG has some nutrient free stuff but generally their product line just isn’t geared for us cannabis growers.