So I recently watched Due Date. It wasn't as funny as I thought it was going to be. It wasn't bad. I don't think it ranks up there with The Hangover and Wedding Crashers but there was some funny parts.
The characters in comedies like these are never really defined. I couldn't tell if Robert Downey Jr.'s character was a Jackass or just a regular guy getting annoyed at irregular situations. And I couldn't tell if Zach Galifinakis's character was rude, dumb, high or if there was some sort of chemical imbalance wrong with him. Also, if I was trying to get home to my pregnant wife who's due date was like 4 days away and this one guy kept it nearly impossible for me to get home (including shooting me), I would have probably left him for dead. But it definitely had some funny parts, and it tried to be funny all the way through which is what you want from a comedy.
Ultimately, I think it's a remake of Plane's Trains and Automobile's, just not as funny. Hopefully, it's one of those movies you like better the 2ND time. Yup Yup