Possible spoilers below:
I've literally just finished watching Human Centipede 2 (Full Sequence) and it is one sick little puppy. The first half of the film leaves you wondering what all the fuss was about. If you've seen Centipede 1, then it's pretty much a load of clips from that with a few other slightly weird sequences chucked in to build the plot, but it's very slow going. The second half however is another beast altogether. The official UK release is cut by over 2 mins and I'm pretty certain that they will almost all come from this half of the film.
I don't want to give away any spoilers but there are some pretty gruesome scenes, including teeth smashing, face stapling and a new born fetus trampled into the floor. The director of this film obviously deciding that shock value was the way forward and it doesn't fail to deliver.
In all, this is not a good film, by any measure, but if you want to see more of the same from C1, with extra nastiness thrown in for good measure, you'll be on to a winner to watch this. Let's hope this is the final installment of this series now as it feels like it has run its course. Something tells me it isn't though and we can expect more to come very soon.