For stereo, the HDTracks version is the best overall. I still need to compare to the 5.1 mix downmixed to stereo, however both of those have the same dynamic range. The only difference would be due to variance in the mix.
If you have a 5.1 system, definitely playback the 5.1 MLP DVD-A. It doesn't use the rear channels a whole lot but certainly lets you pick out more details give the additional channel width.