These book were VERY popular with the 4th & 5th graders at DD's school last year. I read a couple of them - just because I had run out of any other reading material. I found them amusing because they were so preposterous! DD's response was pretty much the same. . . a couple were okay, but then they wore thin.
One of her friends told me that her mother wouldn't let her read them because she saw "no reason to read something so depressing." She borrowed a book from a friend & said she thought they were dumb - "but dumb enough to be slightly funny."
Definitely not the majority opinion, but . . . .