Thank Oprah for the series even making it to completion when it did.
She did one of her shows about The MTM show, gave away copies of the then-released sets, and basically caused enough of a stir to get Fox off their asses and back to finishing the series.
Now, granted, if they hadn't, odds...
The one dual sided disc in season 2 is now single discs in the complete set, IIRC.
S1E10 (the Christmas episode) is missing footage because of a song.
Otherwise, the price is the only major difference between the single sets and the repackaging.
This complete series set was originally due out...