There was absolutely nothing special about the setup, storylines, or writing of the original "Magnum PI", its success was entirely due to the good looks and extraordinary charm of Tom Selleck.
So they're keeping the ordinary setting and storylines and presumably the ordinary writing... and replacing the one Selleck that made it all work?
I disagree.Most 80s action shows were all about the story of the week and had very little depth or continuity.For an 80s actioner i thought Magnum had above average writing and very good story telling.And a great cast in general.Selleck and Hillerman were the ultimate 80's odd couple and had pitch perfect chemistry with each other.Sellecks charm and good looks were certainly a big part of the shows success but saying it was the only reason for the shows success is really selling the show short.
That being said the reason i don't thing a reboot will work is because i doubt they will be able to recreate that same chemistry that the original cast had.Especially Hillerman and Selleck.And also being on CBS they are most likely going to retool it into a generic procedural type show as they do with all their shows.