I just went through and beat all the levels, about to head back and grab all the shoes, as well as starting out on some multiplayer. 
 
However, the beat 3-14 without touching the ground achievement is crazy... I want it, but I can't even comprehend beating a level that late in the game with no deaths. Since a lot of the later stuff is trial and error style (each time you start from your checkpoint, you get a little farther, then something crazy flies on screen and kills you, and you start again with new knowledge allowing you to go another 15 seconds farther), I found myself spending 10-20 minutes on levels with only 7 minute goal times =/. 
 
I hope they add DLC that puts levels on Star Road... also, last boss fight was funny but horribly disappointing (does that Devil May Cry style "change the entire game genre for the last boss fight") I thought that the fight was just about to start (considering the complexities of the other bosses), when all of a sudden I got the achievement and the credits rolled. 
 
Until then, multiplayer is pretty boss.

You're not done until you've done it on Hardcore, mister. 
 
Get back to work!

Not doing hardcore mode. Seems unfun and stupid. Maybe if I was a highschooler on summer vacation but alas...

I've done the first one on hardcore but this one can forget it.  If the game weren't so flawed I'd do it but you can't even see where your are half the time.  Such a let down.

The achievement for beating 3-14 actually isn't very hard. The level is short and once you play through it a couple times you'll notice that it's really a very on-rails level. The only difficult thing is sploding from section to section without touching the ground. At two of the checkpoints you need to have some decent timing to land right on top of a scientist in order to splode your way to the next section. 
 
As far as hardcore goes, I did it in Splosion Man and I'm at the boss of world 2 of Ms. It's a little harder, mostly because the levels can sometimes be insanely long and complicated in Ms., but it's not so much of a pain yet. I can see world 3 being a nightmare, mostly because you'll have 2 or 3 sections in a row that require very precise timing where a single millisecond of hesitation will require a restart. Honestly, they say it's unfair and dumb right in the game, so all the people who've been whining about it kinda just need to shut up, especially the ones who seemingly just want their achievement handed to them.

 Honestly, they say it's unfair and dumb right in the game, so all the people who've been whining about it kinda just need to shut up, especially the ones who seemingly just want their achievement handed to them.

I haven't done 3-14, mostly been trying to up my time in the challenge level at the moment. That and multiplayer, an IRL friend finally got the game.
 
Anybody wish Star Road remained in the game?