If I'm not using cow dung, I mix my own fertilizer with somewhat the same ratios of N, P and K as that product.
But, I pay around 5 bucks per nutrient bucket (2kg's) which will last a year or 10. Most 'specialized' products are built on the cannabis-principle that goes a little like this: As soon as you specify the type of gardening/plant on the label, you can increase the price with 3000%.
With me being a Dutch cheapskate, that just doesn't work: I'm not paying 30 bucks for something I can make for 3 cents and 5 minutes of my time.
There's a general rule that plants push more growth if nitrogen is dosed relatively higher. Flowers can be fed with relatively higher P and K and a bit lower N, however, that is very much disputed by a lot of people. It's true that in agriculture, plants take up higher P and K during seed formation. But that's usually not what we're after in bonsai.
It doesn't matter much in our circumstances. But I want people to see that they're being scammed if they buy high priced, branded and 'specialized' nutrients.