Depends what you want my friend.... Its like asking someone what the BEST candy bar is? Everyone has their own answer.... The REAL question is.... what are you trying to get out of your grow? Obviously you want it to be GOOD.... but, are you looking for BIG Yield? Good Tasting pot? Ease of use? Something cheap?
If your trying to make $$, or want the biggest yield possible.... You want Advanced Nutrients... No question about it..
If you just want to grow a little DANK ass bud that smells, tastes and smokes like the best weed you ever had.... You want something Organic... Either an Organic Tea Recipe, Canna, or Roots line by Aurora Innovations etc....
If you want something affordable, Fox Farm is decent... So is Soul Synthetics by Aurora....
Personally, I use Advanced..... HUGE yields, decent smell, good taste, and DANK bud.... But I also have 10 lights..... This isnt just for my personal stash....
Thats the most honest opinion you will get