Anyone use the Jack's 10-30-20 blossom booster?

Thinking about using it on my next cycle. I wasn't all that impressed with the 7-15-30 finish formula. It just wasn't a game changer. Due to operator error I screwed my plants in the first 2 weeks of flower by under feeding. Got a nasty K deficiency that I don't want to happen again. The blossom booster seems to be a good way to enter flower, but after being underwhelmed by the finish formula It would be cool to hear from someone else that uses it to find out if it's worthwhile.

I’m in the same boat. Using the 321 line and tried the finish last run. My plants wouldn’t take it up. EC stayed the same for 4 days so I dumped it and finished on the 321. Nervous about trying other products form them after that.