Keep in mind I have no nostalgia for these titles and I played a lot of platformers. So I tend to have stricter tastes than others. Anyway...
The first game is last because while a fun game, it suffered from tons of cheap deaths. I played my share of cheap platformers but this game is up there with Mega Man 9 in number of cheap deaths. It felt more like you had to know the game rather than mastering the game with this one. Its a good game that feels very uneven.
The 2nd game is well in 2nd place because it is still hard and has some cheap deaths but the game is still fair(for the most part). This makes the game a lot more fun to play since I don't feel like I have to memorize the levels. The game is platforming bliss. I will definitely play this game more than once. (Unlike the first one which I will only do when I feel like torturing myself. )
The 3rd game is 1st because it gets rid of most the cheap deaths. The vehicle levels keep the game interesting even if the game has a bit too many. The platforming levels are finally getting more creative in this game and it is all for the better. You can tell the developers had no idea on how to make a hard platformer without cheap deaths. When they focus on making a fun game they succeed a lot more.