How do you feel about the UK Justice System?

Forgive me if this offends, but I am a stupid american. What do you think of your justice system and how offenders are sentenced? I recently watched a couple of series, My Lover My Murderer and When Missing Goes To Murder. Are these for real or just reality recreations? I know the stories are based in fact, but the participants? Questions. It seems like a lot of the stories involve people who are far too trusting around other sketchy people. Like the Jamie Lavis story. How does the guy that put two women in a freezer only get 25 years in prison before chance for parole? I mean that guy should never see freedom again, much less the person that kills a child. I understand that the prison system isnt monetized, but how can these weirdos that kill other people ever be rehabilitated? A lot of the people in these stories seem to be a bit drugged out. Not all but some for sure. Whats with the Shaun Dooley narration? Seems weird Anyway I know we are primitive over here but anyone that killed a child or put 2 women in a freezer would never get out. And I know you dont have the death penalty but most of the people in these stories would likely be facing a needle here. I have been to London for work on several occasions and the people have always been lovely, but I have to wonder if you think these killers are being punished enough.