Seriously people, there are multiple excellent board review sources. It seems like every resident I talk to has a preference of which he/she likes, and yes there are some names that come up over and over again.
So this being said, one commonality of opinion is this:read something! Be methodical and intense. I personally do not like the format of Morgan, and it is unpleasant to me, but I know residents who claim they used it soley, and they smoked the boards-hmm my loss I'm sure.
But find something that you like, and the more books you look at, you will realize that the material is the same stuff. Yes some resources are higher yield.
From experience this past July, the sources above do work.
Hope this helps.