For the true "o2tvseries" archival mentality: buy the Blu-ray box set. It includes deleted scenes (the infamous "Earl's conversation" from Season 2) and commentary from Bryan Fuller. This is the highest quality you can get.
"You’re avoiding eye contact again, Will," Hannibal said smoothly, stepping out from the shadows of his library. He held a glass of dark red wine. "Is it the eyes of the dead looking back at you, or are you afraid of what you might see in mine?" o2tvseries hannibal