It really makes a difference when the narrator is good, and this guy is great. He nails accents so well that I knew which characters were Protestant before it was mentioned in the text (there's still sometimes an accent difference now, but even more so back in the 1960s when the story is set). He makes everyone have an individual voice even though many of them come from the same area and therefore have similar accents, and he doesn't do that annoying squeaky voice for women that some narrators do.
I like it when they put a bit of effort into finding the right narrator. I started listening to a book by a Dublin author and they had clearly just asked the narrator if she could do an Irish accent and not checked. So the narrated the book with a very RP English accent and did the dialogue in a Belfast accent, it was a good Belfast accent but these people were living in Dun Laoghaire/Dalkey/Killiney. She also cocked up by saying Dun Laoghaire in the Irish way when she was speaking English (like someone speaking English but saying Paree instead of Par-iss). When she started calling the Gardai the guard-i instead of the guard-ee I gave up because I realised I was so annoyed by the narration that I wasn't following the plot.