Have both. The picture quality is a bit better on Blu-Ray, the audio (depending on your setup) is far better on the Blu-Ray (DTS-HD vs Dolby Surround 2.0 - no contest). I don't remember the extra features being exactly the same, but definitely not so much of a difference that it would be worth buying it for that. I mainly purchased the Blu-Ray for it's superior audio and better video. Again, depending your set-up is that worth the extra 40-50 to buy it again? Only you can answer that. Either way DVD or Blu-Ray, a truly great show.
The only minus of the Blu-ray is that the effects shots aren't actually better on the Blu-ray because they weren't rendered in HD (Fox wasn't broadcasting any kind of HD at the time except perhaps sports), and no one wanted to spend the extra money to re-render them for this package.
I think they look fine, honestly, and since the show intentionally made the effects look less than pristine, the lower resolution actually fits the style.
I need a bit of help, please. I just put disk 2 in to see if it was ok, because it was floating around in the package, and all the backgrounds look very grainy and fluctuate a bit. It is disconcerting and I am extremely bummed. There are tiny little scratches on it. Do you think it was the scratches? Should I send this back and ask for a better copy? Or is this as good as it gets? (Please not!) Should I get the high definition version instead? Only I would like to play it on a standard def TV as well as my MacBook screen.
It was a "used" copy but came shrink-wrapped and looking brandy-new other than the micro-scratches on the one disk. Will preview other disks when I get back later, I wanted to post this now to see if anyone knows what's what already. Order details below. 1 of: Firefly - The Complete Series [DVD] By: Nathan Fillion, et al Condition: Used - Like New Sold by: Source Media Group (seller profile)