I have read a few and they were, as some people have commented, okay.
My mother used to read them a lot, along with other historical/religeous fiction. She seems to have gone of them since I gave her a Kindle for her 85th birthday.
Now it is all Jack Higgins, James Patterson, Elmore Leonard etc. with an occasional Margery Allingham or Rex Stout thrown in.
According to her (she lives in a very small town) she didn't know where to get the (quote) interesting books.
To think I could have been mailing her a box a month
Helen