Really? That's funny. I haven't watched it yet but both my brother and I loved Shaun of the dead, and Hot Fuzz but he said this movie was so poorly done that he actively tried to forget that it was made.
I thought it was great. I saw it in the theater, and the plot swerve wasn't advertised beforehand, so I REALLY wasn't expecting what I got. It's so over the top that, in my opinion, it crosses the line twice and comes out hilarious.
It's also the only time I ever got remotely emotional in the C&B trilogy, as one of the scenes hit particularly close to home with upsetting simplicity. I highly recommend it; it's worth the rental if nothing else.