The bottom line here is, Poirot is a very well developed character, with a good supporting cast, which leads to many entertaining crimes being solved. Yes, it is a bit of a procedural, but the tales were developed in the days before it became a commonplace television genre. Written by one author, there is a singular vision and a detailed world in which the stories can play out. Liberties have been taken in these filmed versions, of course, most signficantly by mixing up the order, and moving some around in time by ten or twenty years. But the core of the character shines through, and Poirot proves higher quality than many of the CSI and NCISs made today that owe it dues.
Poirot The Early Cases Collection has no special features. This isn't so obvious when plowing through forty-seven hours of episodes, a huge amount by nearly any standard. Because Poirot is what it is, one likely won't miss the extras much, even if it would be interesting to get Suchet's take on what the series is, and what it means to him.
Is it necessary to buy Poirot on Blu-ray, rather than DVD? Honestly, not really. As someone who likes to get the best possible quality available, I am happy to have the Blu-ray version. But considering that these are 4:3 remastered versions with only 2.0 sound, there probably isn't a huge difference between the two. There aren't many special effects, although high definition should bring out the rich details in the costumes and settings, which are worth praising, better. That aside, te colors aren't particularly stunning, and there isn't anything I noticed that really screams for HD. The Blu-ray probably offers a bit clearer picture than the DVD, but that's about it. I do not have the DVD for comparison, but the impression I get it that Poirot can probably be enjoyed in either format almost equally.
Agatha Christie's Poirot The Early Cases Collection is available now from Acorn Media.