I recently started playing this game. It is undoubtedly more challenging than Baldi's Basics, and its atmosphere is vastly more perturbing. I love it!
I do have one complaint, however: the jump scares are way too loud. I am tired of turning up the volume so I can hear certain parts of the game (e.g. Mr. Mix's heavily-distorted, nearly-unintelligible voice) and then rapidly turning it down again so my eardrums don't get blasted into the sides of my brain when Mr. Strobovski's face jumps through the screen.
Apart from the sound issue, this game is awesome! I dig the design, the disconcerting ambience, the difficulty, and pretty much every other aspect of it. I especially like how Viktor is chasing you even while you are finishing the math assignments; it adds an extra layer of urgency the original game lacked. Can't wait to beat it!