No word on the Rothfuss (haven't really been interested in him since the second book wasn't that appealing to me). As for the Malazan, I'd say try the first two (since the first is a bit different in some ways than the others, although latter volumes refer back to it). If you don't like it by then (and both should be easily found in used bookstores), then the other volumes likely wouldn't be to your liking.