Black Clouds & Silver Linings.
TCOT is great and ANTR is good, but the rest is pretty forgettable to me. Outwith the 'top tier' songs on each of the other albums, there are also plenty of decent 'second tier' songs too - eg. Constant Motion or The Bigger Picture.
I don't feel that with BC&SL. It could have done with some serious trimming and the time that saved being used on another track or two. Of course, there'd be no guarantee that any additional tracks would have been any good anyway.