I think the major differences are perlite vs verm as well as the Mychorrizal innoculant. Myco makes everything grow better. I like perlite better too but I use both. I don't buy mixes very often though. Its cheaper to just make your own super soil. Peat, perilte, vermiculite, worm castings, blood, bone, guano, myco, and lime always grow TREES. The more aerated your soil is the easier it is for those roots to become super nutrient highwaysa major part of it though is the promix these have by far out grown everything planted in jiffy all receiving the same ferts and in the same conditions, I am now a believer Promix BX