Nasty. I saw the entire series a long (long) time ago, but failed to review all the episodes back then. A good excuse to rewatch the missing ones, as these films did leave quite an impression. Not that I thought they were excellent pieces of film making, but they sure are memorable horror shorts.
The films are little more than an excuse to put some realistic gore on screen. The guys behind the Guinea Pig series were effects people, and they simply needed projects to put their skills to practice. That explains why these films look quite cheap (and were in fact mistaken for snuff movies, by none other than Charlie Sheen), but the gore is pretty damn effective.
Devil's Experiment offers nothing more than a woman being tortured. It starts quite tame, with some slaps and kicks, but before long they're pouring maggots into her wounds and needles are pierced through her eyes. There's really nothing beyond that here, so unless you're a fan of grim and dreadful horror cinema I wouldn't advise watching this. I do have to say it's still surprisingly convincing for a 35-year-old film.