Interesting many people saying the Pratchett books improved over time.
I read "The color of magic" many years ago in my school library when it was the only book Pratchett had published.
I loved it and over many years I read quite a few of his books, but I suppose by about halfway through the books he wrote I lost interest.
I don't know whether I just got sick of his style or I preferred his earlier books.
but as I remember it, I seemed to enjoy the earlier books more.
Not sure I'll bother reading the HHG books again.
Having read all the books.
Listened to the radio series (on CDs).
I had the records at one stage.
Saw the TV series.
I even watched the movie, which contrary to popular opinion, I tried to watch with fresh eyes and actually enjoyed it.
I even had the text adventure computer game, which I didn't finish, but it was kinda fun.
All in all, I had a laugh and I expect, as already has been commented, there are probably some very high expectations of it, which I doubt it can live up to for many people.
It wasn't some life changing experience for me, but I enjoyed it and there was some very insightful stuff in there and interesting social commentaries.
Beyond that, the style of the humor is not for everyone, and that's completely fine.