Why is it important to watch such a movie? It's not funny for most viewers, except for hardcore horror fans, they get the in-jokes and the references. Razor is almost boring as a movie, but extremely intense as a documentary with re-enactments of torturing sessions. So what the hell is it?
A movie doesn't need to be part of a genre and to represent it. Slasher is a sub-genre that became popular in the late 70's and early 80's and found new life with Scream and later with Saw and Hostel. Razor isn't a slasher, it plays around the whole idea of creating a slasher and intentionally pretends that viewers are mostly stupid, it is academic trash and the most clever stupid movie you can find. You will get attracted to watch the whole thing, you will hate it, but you will not be able to forget is somehow. There are some hidden ingredients inside, that will make you enjoy the fact that you are hating it while watching it, you will see the potential and you will hate the fact that nobody tried a bit harder to turn this into a real slasher. But you are missing a very important information. This was done exactly like the 48-hours short movies. The principal photography (about 50 minutes of the whole movie) was done between 9 o'clock on a Saturday morning until 8 o 'clock Sunday evening, with no pause and no breaks. The actors went for it and supported it. The torturing sessions were done with appointments, during the following week. Is this important? Shouldn't they take more time and put more effort? Yes and no!
The original script was hated so much by so many people, that the director chose to just use the basic idea and to shoot around it, with actors improvising. It wasn't meant to become a comedy or to have dubbed dialogue. The original script was a very disturbing movie, where everyone inside had his/her own perversion and everyone was involved in a different crime and murder. The original was close to Bay of Blood, the mother of all slashers. The plot involved real BDSM, bisexuals, slaves, transgenders and real incest with twins. Some of those elements survived in this simplified version, with some mild bondage, the incest as an act, and the killer using the dildo to hit people's faces, where in the original script he used it for penetration. The reactions from people were so extreme, that even in public places they start shouting and crying, while they were discussing the plot with the director. It is unfortunate that the whole thing turned this way, but sometimes you need to take a decision and to start shooting. Razor is still kinda extreme for being a slasher comedy, but at least it is not the most extreme disturbing thriller of all time, like it would be. Now that you know, you might watch it with different eyes...