Still not available on Blu-ray, so this is the first time you can own on HD. I bought the complete series via iTunes for $79.99, which seems reasonable to me. Individual seasons are $19.99. Previously, this was available via on-demand from Hulu. I have most of the seasons on DVD, and the extras from those discs do not appear to be on the digital versions - as best I can tell. Also, the aspect ratio is 16:9, not original 4:3. But to my knowledge, there is no way to watch/get the OAR in HD, so it's a catch-22.