How bad is it? It's possibly the worst werewolf movie (and I liked Werewolves on Wheels).
Should you see it? Yes. The MST3K version is probably a good bet, though I haven't seen it.
Archaeologists in Mexico discover the bones of a werewolf. Whenever someone gets cut on the bones, they become a werewolf. This is extremely sloppy and appears to have been filmed over a long period, as one character's hairstyle keeps changing. Another character just disappears part-way through the film, without explanation. In the climactic fight scene, there's never a two-shot: you never see both characters on screen at the same time, so they must've been filmed separately and then edited together. There's a transformation scene that takes so long that I felt my own hair growing. One of the major problems (besides the script and acting) is that at least one character appears to reciting their lines phonetically and doesn't know what their character is supposed to be doing.