I've never used those nutrients before,but i did a search an read up on them,I think that part A would contain the micro and secondary ingredients,part B the major,they seem like a fine product,I wonder if i can find them in the U.S.?I havent used the PK13/14 either,but my hydro shop has it in stock,so on my next grow i'll give it a try.I only use superthrive very early in the veg cycle and to start cuttings,I've been told that it slows growth in the flowering cycle,but i never knew why?but if i were you,i would just keep using the manufacture's directions for everything,it's been working out for you so far,I wouldn't change a thing,whats the ph and ec of your reservoir?just curious....bonbon