Review Summary: For Knife Party, it's a B. For the dubstep/brostep industry in general, it's a big fat F.
I'll admit that I'm not very familiar with Rob Swire and Gareth McGrillen's work in Pendulum. I won't use that as a way to write this EP off as a complete bomb with the hipster philosophy "it was better before it was mainstream". However, I will be judging it based on what it is as a brostep/dubstep/whatever the hell you want to call it EP from two competent artists.
The title track, "Rage Valley", is probably the worst of the four. It's a grating brostep jam that sounds WAY too much like Skrillex for its own good. If there's anything redeemable to it, it would be the first post-drop segment, which actually sounds like something I would listen to. Too bad the rest of it sounds like an uncoordinated mess of noise. "Bonfire" is a surprising jump in quality, offering some catchy reggae-ish beats and a pretty decent drop. Unfortunately, everything comes crashing down with "Centipede", which starts out pretty good, using a sample about a nature program about a big-ass centipede and ruining it with scattered, ear-bleeding melody. Finally, we have "Sleaze" which is so boring and lifeless it's really not even worth talking about. It's pretty much the same as the title track, but it has coherent lyrics. Shame that they should waste it on a party song that feels like the hangover you get after the party.
It's not Knife Party's worst work. Certainly not. It's much better than Abandon Ship, although that's not a very high bar to raise. I could make an album better than Abandon Ship with Ableton Live Lite. What this album proves is that Knife Party is the attempt of two men to split Skrillex into two different people. If you see Rob Swire walking around in black shirts with one half of his head shaved, don't be surprised.