I ran it for about a year. Aside from the metals, I didn’t like how you use the same nutrients with the same ratios in veg and flower. I felt like Jack’s goes overboard on N to get PK numbers up in flower. Towards the end I was adjusting the 321 ratio and considering using a different source of calcium to cut out as much N as possible. There’s a bunch of posts of me talking about it over at RIU.
Canna is the same with two parts all the way through, but everything seemed balanced and I never had any issues. I could also run it at a really high EC with frying my plants.