I just finished my first run through. (Took me about 3 1/2 hours.)

Went with The Scientist, The Hill Billy and The Adventurer for the first run and aside from some backtracking and imprecise jumping controls (only at times), I really enjoyed the game.
 
It's a bit short, but hey there's at least two more playthroughs in there, and I thought it was rather easy (apparently The Time Traveler has some tougher puzzles). Art direction and humor are rather good as well, but now that I heard, that the Cave used to talk more in an earlier build (as said in the QL), I really wish it still did, because there's times when you run around swapping characters/items and there's next to no sound. (The music isn't worth mentioning.)
 
Anyways I already started my second run, which is something I rarely do right after finishing a game, so it's definitely worth checking out.
 
So what are your impressions so far?

I sorta broke the Knight scenario by never opening the dragon gate (which makes the story make no sense). I'm not really sure if it's supposed to be possible to do that (can the monk just grab the coin?), but the way I did it seemed a tad exploitish. Went through the adventurer area which was sorta meh. Not really very puzzly just a lot of following instructions. I'm currently stuck in the time traveler area though. It's sort of a bitch. Very expansive area (considering it's 3 similar versions of one area about as big as the other character specific ones) and barely anything you can interact with. Feels like I'm doing more travelling than puzzling.

My biggest annoyance so far is that it really feels like I'm missing a lot of stuff. I get that it's areas I can go to with other characters, but it would've felt better if it wasn't so obvious. It sorta feels like if you do the "wrong" character picks you can go for a long stretch just passing by area after area and nothing is happening.

Edit: Found the solution to where I was stuck and it was sorta BS. Basically it was something I had tried several times, but hadn't done the exactly correct way. Also, I managed to crash the game =(

@Sessh said:

I just finished my first run through. (Took me about 3 1/2 hours.) Went with The Scientist, The Hill Billy and The Adventurer for the first run...

Hey, that's my same team!

Damn, the carnival is full of little puzzles. Stuck on the wheel of misfortune, will have to sleep on it lol.

Im into it so far. My team is the knight, adventurer, and the twins. I missed about 3 of the adventurers cave paintings bc i assumed that symbol was the monks for some reason...

Protip: if you see a cave painting, anyone on your team can activate it.

Played through a run with Time Traveler, Twins and Scientist. The game was interesting and moderately enjoyable but I felt the stories that I encountered were a little weak. I started a second game with the Monk, Adventurer and Hillbilly but stopped once I got about 15 minutes into playing through the exact same thing I had just played through before. Hearing the cave jokes a second time around (third time maybe since I watched the quick look) just didn't do it for me and it also made me realize how much backtracking there actually is running characters back and forth due to their one item limit.

Bottom line

The game is enjoyable one time through and the individual stories I encountered weren't strong enough to make me want to play through it a second time. I think this game would be a solid $5 to $10 dollar value but feels over priced at $15 for the amount of content it provides. On the scale here, I'd say it's a solid 3/5. Pretty much, Alex nailed it with his review.

As mentioned before, time traveler has the tricky ones, I just played through the time travelers and it really got me thinking. But the game is a nice and mellow game you could mess around with even if it does not follow the standards of your traditional adventure game that maybe Gilbert would create. Actually now that I think about it I'm really glad they went this route, its refreshing and this is a way for them to deliver a specific genre in a new and refreshing way.

The platforming is easy, sure the controls in some areas are a bit choppy but then again I'm nitpicking. Impressions are generally good since the game is at the price point it is and there is obviously a lot of replayability.

I'm about two hours into a Knight, Twins and Time Traveller co-op run. Been really enjoying my time with it! Loved the Twins section. Dark.

@Ares42: Moving the rolling boulder out of the way? That was one of two puzzles (the other being capturing the voice of the monster) that I felt was ruined by some strange control decisions. Knowing you had to keep holding down the 'grab' button while changing characters was not intuitive. From the Steam forums, it sounds like this is a common place people are getting stuck.

@CloningMishap: ye, pretty much.

Yeah, I don't like it. To much bland platforming, to many puzzles that are easy to figure out but takes so long to get from point A to point B (largely because you have to do it 3 times), and I didn't find it that funny or at least not funny enough. I can't see myself playing it again to get 3 more stories which is another problem, why 7 characters? If you have to play 3 times to get all the stories make 9 characters or cut it to 6 so at least the numbers work out.