It was recently on sale on the XBLA as well, so I'll vouch for that. Played through solo on PC.
It's really great fun in co-op, especially if you have a lovable oaf playing... the lovable oaf knight. Gag reel highlight quotes: "No, see, if I hit the cubes he makes with my hammer, it lets him make another one for free!" "Guys! I found an easter egg! I think! It's a plank! Like from... Dead Island? *beat* YOU CAN MAKE THOSE!?" "These... These... DAMN GAMES DON'T PHYSICS!"