Close to $600, but I've got enough nutes to run 2 possibly even 3 grows. Their Fire PK Booster is what really hits the pocket book. A liter was $160, but you only use 1ml/gal thru most of flower, and I probably have enough of that to do 4 more grows, so hard to give you a real cost/benefit analysis, but I will say, I've run about 5 different nutrient lines now (Canna, Advanced, GH, Bontanicare CNS & PBP), and this was by far my favorite to use.
I don't really think it's that much stuff to be throwing at them. No more than any other synthetic nute line running their full lines. In fact, I find this line amazingly simple to use.
It's hard to say without running a true side by side, but I definitely feel like this is my best crop yet. Some of that may be due to just familiarizing myself with different strains and becoming a better overall gardener in general (just being able to read the plant).
I've done organics, and I like them a lot, especially the taste, smell, and texture of the flowers, but for me personally, following a feeding chart as a guide allows me to make sure my plants get all the nutes they need throughout flower, and is just simpler for me.