Shitty jump mechanics and beginners traps make this way more frustrating than it needed to be. The music and feel of the game are amazing. The rest of it falls apart when you need to make a pixel perfect jump.
Practice mini-jumping too folks. Even though the game doesn't tell you you'll need them. Or that they even remotely exist. And the ending doesn't even make you feel like you got a reward. Yay. He made it into heaven with a knife behind his back.
There's challenge and there is frustrating due to bullshit. This game is the latter. Did you have anyone play test the controls before you even put this out? That's the most important aspect of any game: being able to actually play it.
And the last level is literally just like that robot chicken skit where you have to die or be extremely lucky to know what's up ahead. As if that level wasn't annoying enough, you have to do it blind.
TL;DR: Amazing feel behind the game, terrible controls for what you need to do to beat it.