windowflow just keeps getting better and better.
the developer is *very* responsive, to either bugs or suggestions; he also seems very keen to keep his product alive and growing.
in a couple of versions it will definitely be ahead of other window managers, but then again, it's all a question of personal needs -- my window management needs are fulfilled by windowflow and i'm a loooong time mac user.
i've tried many of the other window managers: i miss windowshade which i shall not update because of the new rosetta requirement; and even though i usually really like apps by manytricks i never liked witch; and the others left me with a feeling of Windows-inspired utilities.

(i am in no way related to this developer; just a happy user)