I enjoyed Mega Man 3 up to the Doc-Robot stages where it felt like the game took a turn for the worse. The robot master stages of this game are great, and finding out the optimal boss order by myself felt rewarding. None of the robot master fights felt like BS, at least with the correct weapon in my arsenal.
Too bad I can't say the same for the Doc-Robot fights. Bosses with unavoidable patterns are the bane of my existance, and the Air Man fight is a prime example of this. Dying and having to go back to the start of the stage for trying to experiment with the optimal weapon to use, merely because the tornadoes decided to form an unavoidable wall did not feel great at all.
The final boss was a disappointment as well. It was just bad.
This was however the first NES Mega Man game I've finished without the use of save states, and I consider that to be a great personal achievement, so yay!