I don't know Blake's 7. But 'crappy' effects reminds me of Clash of the Titan, the 81 version. The stop motion was crap, but magical at the time. Still is. Bah... people are so misguided.
If you like dystopian scifi and do not mind the Queens English it is well worth the watch. I like anything from scifi to drama and even some musicals and recently one of my best friends who is a script rewriter got me into reading scripts instead. That's a whole different experience: it is quite nice for me as I have a vivid and graphical imagination. Very different from books. It however does make the average production seem even more cookie-cutter.
Edit: I do not think I watched or read Clash of the Titan '81 so I will.
The only english scifi that I know is ... red dwarf. I'll Blake's in mind in case I'm into 'new old'.
I guess there's a time for visual bliss but like many things it wears off if abused. Today is more about large scale SFX and not enough of the rest. Reading is low on visual and has to be high on the rest. I did read few pages of scripts and found it very interesting too, but maybe for historical purposes (seeing drafts of Terminator, Alien, etc)
If you like greek mythology and shiny metals you'll probably enjoy CotT. It's not Kubrick's mastery worth, but it has a glow of simple magical, fantasy, that I rarely, if ever, found again.
