How bad is it? It's dull and near unwatchable.
Should you see it? No!
Well, on the plus side, this is a better existential boat horror than "Beneath the Mississippi," which makes it slightly better than getting cholera. It's not as good as "Ghost Ship," though. A kid gets a boat as a gift, takes his friends on a ride, they drink and have sex - and eventually find that the weird smell is a dead body. They all say what their biggest fear is and then that fear destroys them, after the kid drowns. It's really slow.