The last series of Blake's 7 was far from a masterpiece, in fact it was a bit of a shame to see it kind of go downhill the way it did before it finished. After the strong first two series and a reasonably good third series, Blake's 7 was apparently finished on TV until they renewed it for another series.
In a way its a shame they bothered, cos quite a few of the episodes here aren't the best. "Headhunter" "Animals" "Power" are pretty so so, but the award for the worst episode goes to "Sand" which features a little bit of a romance between two of the most unlikely characters. Written by Tanith Lee, this episode belongs to a Mills and Boon story not Blake's 7! No offence, but she should have been kept well clear of Blake's 7.
But its not all bad, Glynnis Barber is pretty foxy as Soolin, the new crew member, Paul Darrow is still as ever watchable as Avon, even though he is posing more than acting! There are also to be fair some really good episodes here too, "Rescue" is a good opener, "Gold" and "Orbit" (which features Avon at his most creepy!) are also both excellent. And the finale "Blake" is a great episode by any rate, and also a real shocker to go out on, with the last five minutes being some of the best you'll see in the history of the show, its also great to see Gareth Thomas reprise his role as Blake (his solid acting is missed!).
On the extras side I was bit disappointed by the lack of commentary tracks, as there were only 2 episodes, Assassin and Blake. Its a shame they didn't pick a better episode to comment on like Orbit rather Assassin.
So series 4 is a real mixed bag, but its not all bad but not all good either, if you want to get it for completive purposes then I would recommend it.