I'm not even sure the exact date when I started (sometime in February) but I'm completely finished the HSK 6 deck (linked previously as the Timo Deck). That's a total of 5000 words, 2663 characters, some odd idioms, and who knows what else.
My reading is pretty decent, my pronunciation has improved tons, and it creates a wonderful base for building listening, writing, and speaking ability going forward.
It's been 25 new words a day, everyday for the last 4 and 1/2 months. In the last month, maybe it was just the psychological aspect of nearing the finish line, but words started slipping a lot and my review deck was as high as 300 cards a day plus the 25 new words. It took on average about 70-80 minutes, many times 90 minutes a day of just flash cards. But, now that I'm finally here, I can 100% say that it was worth it. Of course, I'm not completely done. Over the next few days/week I will still be studying the review cards that will slowly decrease to negligible amounts over the next week or so. Really excited for what comes next.
Now comes the fun part, massive input :D Three months to go before HSK 6!