it's pretty short and sweet, difficulty wise, it's on the easier side if you know what you are doing.
the game lacks shortcuts tho, so you better put up with a lot of backtracking. there are also a lot of pointless locked doors, i just dont see a reason for their existance.

most of the puzzle are simple, with one exception (the clock one which i had to brute force the solution, maybe because I'm a dumbass)

for a 3 hour game, shorter if you have good spatial awareness and good with puzzle, I'd say its worth the price