There’s no real way I could say this better than The Scientific Gamer, so I’ll just link to his article and you can read it there. While you’re there, subscribe to his site. It rocks.
Far and away, the biggest problem with Hack, Slash, Loot is the fact that you can’t heal. If a patch solved this one problem then the game would be great. It’s a deal-breaker and it’s why I’m so sad about this game because it’s so neat otherwise.