It is interesting how polarizing the butterfly mechanism is. I absolutely love it. I can type more accurately and faster on it (they keys feel more stable) and I dread when I have to use an external keyboard with the old scissor switches or a pre-butteryfly MacBook. My colleagues who have a new MacBook Pro also prefer the new keyboard. The only large downside seems to be that it breaks more quickly.

Of course, in the end it is a matter of taste. It would be nice if Apple could find some compromise between the new and the old design. But Apple being Apple, they will stick to it ;).