Why would it being more recent mean it had better bitrates? Until I see evidence of that I'd be skeptical. After the debacle with the 2004 editions and now with the problems with the blu-rays I won't take any of that for granted when it comes to quality.
The only thing I'm willing to bet money on is that the 2013 dvds are the same "cuts" as the 2011 bd's.
From what I've read about the audio commentaries, the "new" commentary is simply audio spliced together from old interviews and specials. That's a nice idea of course, but I'm curious what (if anything) they stripped out of the DVDs to make room for that additional track.
Incidentally I'm a bit surprised that the "bonus discs" for the 2011 set are actual blu-ray discs, not DVD9's, even though the visual quality looks like dvd.