Just watched all 6 episodes of Prime Suspect 1973 and enjoyed it, despite it being written by Lynda La Plante.
It did actually have the feel of 1973, they got the cars and the clothes right. Music was a bit hit and miss though - Roxy Music; Tubular Bells and Dark Side Of The Moon - correct. All that sixties stuff was not correct though.
I was about that year in my early twenties and managed to get both stitched up and beaten up by police officers in that year, I swear they weren't as nice and as straight as those in the TV series back then. And I don't recall ever seeing any black coppers in '73, let alone a black CID officer and I'm not sure whether white CID officers would have worked so well with a black colleague. I'd like to think I'm wrong thinking that but I'm probably not wrong.
I think in some respects 'Life On Mars' was more accurate in capturing attitudes in the seventies.