Reading up on it, I see that the problem was the "Director's Cut" wasn't actually Ridley's... he didn't have much of anything to do with it. So I can see how he'd want to release a final definitive version of his own.

On the other hand, from what I've read, the differences are small and mostly atmospheric.

The documentary disc, though, might be worth the price of admission for the 2-disc set.

Really, the only thing I would have changed from the Director's Cut release would have been to digitalize-out the wires on the flying cars. That's the only thing that ever bugged me about the film in the first place, otherwise I thought it was perfect. I don't hear any mention about that kind of lucasing in any of the reviews though.