We got Lionheart at the budget price of SEK 69 ($10.50), and after I sipped the singleplayer game we decided to try it during last weekend. The games schizo nature is reversed in MP in my opinion.
The first part (Barcelona) plays a lot like Baldurs Gate, a solid singleplayer RPG. But it is (just like Baldurs Gate) a bit slow for multiplayer since one character will do the talking and the other be a bit passive. There is also some backtracking across town, which takes time even if it is handled much better than in the infinity engine games.
The post-Barcelona game is more like soloing Icewind Dale, wading through enemies in a linear fashion. But having two players give you many more tactical options, making this part much more entertaining in multiplayer than in solo.
And while the game doubles the number of non-boss enemies in MP this actually makes the game easier. Both players gain full experience for every kill and quest, and since you both can specialise the characters more (my gf is an archer/diplomat, I am a 2hander/thief) and gain almost twice the experience you end up unhittable to many enemies that would have been troublesome in singleplayer. This makes the number of enemies moot! So while Dungeon Lords had some odd MP mechanics it is much better balanced for MP.
In the end I think both Dungeon Lords and Lionheart are better in MP than in SP, with the first being more intense and the second having a more interesting setting (I am coloured by being a history buff here). I'd give both 3/5 for SP and 3.5/5 in MP, making them well worth a budget price...
BTW: Dont try to make sense out of the subjective line drawn between the second half of Lionheart and Diablo (which I dislike). I cant explain my strong preference of one over the other using rational arguments
