I just got this set, and I've been comparing it with the different versions of the Dickens adaptations available here. First, all of these are somewhat old; the most recent is 1998, Our Mutual Friend, and that one is also the only one in 16:9 format. The Bleak House, for example, is not the 2005 version.
However, even within the same versions, there are some disturbing bits of information. For example, Our Mutual Friend does have the same actors as this one:
http://www.amazon.co.uk/Our-Mutual-Friend-Paul-McGann/dp/B00005KB4G
but, according to the box, is 255 minutes long, compared to 350 minutes for the separate version.
David Copperfield is a 1986 version, not this one: http://www.amazon.co.uk/David-Copperfield-DVD-Emilia-Fox/dp/B00005KB4E
Nicholas Nickleby says 300 minutes; this version (http://www.amazon.co.uk/Nicholas-Nickleby-BBC-Nigel-Havers/dp/B000B73HIO) says 325 minutes.
Tale of Two Cities is 200 minutes; this one (http://www.amazon.co.uk/LITTLE-DORRIT-TALE-TWO-CITIES/dp/B004Z5GUT6), with Little Dorrit (not included in this set) is 680 minutes.
In short, at best these are cut-down versions of the BBC productions, and some of them are old ones, that even the BBC no longer sells, either here or on their web sites. There's really no way to know this, but I find this deceptive enough that I'm planning to return this, if Amazon will pay the shipping (I live in France, and return shipping might be nearly as much as the set cost.)