Well, it wasn't excruciating. In fact, compared to other hip cinematic updates of classic TV shows, it's pretty damn good. That's not to say it's actually, you know, good good. It's as formulaic and manufactured as every other movie in this peculiar subgenre.
But it is, for the most part, well manufactured, thanks to Michel Gondry -- just about the last person you'd expect to make a movie like this. He directs action better than most -- exciting, original, and coherent -- and adds enough fun, quirky delights to make up for an excess of Seth Rogen being Seth Rogen.
Rogen's a sharp comedy writer, but not when writing for himself. The movie's best jokes either don't involve him or don't give him the chance to fall back on his usual shtick. It's a brave choice to have his character start the movie as a rich, self-entitled douchebag and end it as a rich, self-entitled douchebag to everyone but Kato -- but it doesn't work because the movie always wants the audience to like him.
Luckily, he spends most of the movie with Kato, who kicks all kinds of ass. Jay Chou, with a tenuous grasp on the English language and charisma to spare, saves the movie. Also, Christoph Waltz does the weirdest riff on the thankless action-comedy villain that I can remember. I'm pretty sure Gondry's only direction to Waltz was, "Do what you did in Inglorious Basterds, but add some ham on top."
There's enough solid jokes and car crashes to make it worth watching -- and the 3D conversion is better than most -- but that's about it. And that's not necessarily a bad thing.