Brother's Grimsby was hilarious. Funniest movie in a long time. If you are a fan of SBC you'll love it I would say. It's not as good as Borat or Bruno but better than Dictator and the Ali G movie IMO. Some jokes fell flat of course, but it has some pretty huge laughs as well. There were only about 12 people in the cinema when I watched it, but everyone who was in there was cracking up.
Edit: I only see maybe 3-4 movies each year so my opinion isn't worth much probably. I don't stay up on movies and watch trailers and all that crap, in fact I didn't even know there was a new SBC movie until last week when there was the Donald Trump AIDS thread and decided I would go watch it since I love the Ali G show and most of what SBC does.
Also, the trailers before this movie were garbage. There is a movie that's got Zac Efron and some other dude trying to go to a wedding in Hawaii, looks like dogshit but it's apparently a comedy. There was a trailer for a Dazed and Confused 80's sequel/spinoff? type thing... don't know who that one is for it looked atrocious. Popstar looked ok but then I saw Judd Apatow's name and that dude hasn't ever made anything worth watching so I'll skip it. There was a movie about a washed up gymnast, called "The Bronze" I think. That girl's character was obviously supposed to be an annoying, shrill, terrible woman... but after 2 minutes she already was on my last nerve and I'm the most chilled out dude around. If anybody actually watches that garbage I'll be shocked. Long story short, go watch Brothers Grimsby. It's funnier than most other comedies this year, judging by the trailers I saw.