You want to pay $100 for a half season on Blu-Ray. Remember, the 2nd season was only half a season.
I used to worry about mixed cases for Harry Potter and "Nip/Tuck". However, seasons 1-3 of "Nip/Tuck" are SD DVD. Season 4 is HD DVD. I scored it for $17 shipped off E-bay. You can't even get a used SD DVD box set of it that cheaply.