It's nice to hear an album that sends you back to those glorious days when grunge meant something dark and horrible, not a form of sordid pop. The whole point of Grunge was that it was never slick. It was dirty and only produced in as much as the noises made were somehow transfered onto vinyl and/or CD. That was before Nirvana came along, got themselves a real pop record producer and still claimed to be Grunge.
Part Chimp recall dirty grunge rock bands like The Bastards and Bullet Lavolta. They also recall the days when metal was dirty, like the early days of Black Sabbath. There's even some occasional 60s keyboards thrown in for that, stoned, garage band feel.
Rating: 3 skeletal thumbs up.