The Early Years trilogy works better, I think, if you come to it after you've read the rest of the series. You the reader know so much more than Jack and realize what parts these other characters he meets will play in his future. They're different from the main series in that they're dark, gritty crime novels.
The Tomb and The Touch were revised to cut them loose from the 1980s but aren't substantively different. Nightworld, however...you'll need the 2012 edition.
FPW
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