Wow. Really Wow. I'm just going to start off by saying that I've played both Dungeons of Dreadmor and Hack, Slash, Loot. They are both good games, with very different mechanics.
In Dungeons of Dreadmor you have to build your class and level it up in a way so that you can survive the longest, whilst in Hack, Slash, Loot, you choose from a multitude of classes and play that class to the best of its ability by collecting items that compliment the class's abilities. Now normally I would go on, and continue why these two are both games, but you've already heard why Dungeons of Dreadmor is a good game. If you read this you will understand why Hack, Slash, Loot, is a good game: http://www.rockpapershotgun.com/2012/01/24/impressions-hack-slash-loot/ (They explain this much better than I every could.)