Quite bad, but I felt compelled to finish it for some reason, so there must be something that pulled me in and kept me going.
After 2-3 pages, I was convinced it had been written in the 1950s (opening scene of a star-crossed "woman scientist" at a scientific meeting wearing an evening gown for some damned reason). But Google said otherwise. Then I guessed it was intended to be juvenile sci-fi in the tradition of Heinlein, but deaths and cursing soon made it clear that wasn't the case.
It's full of grammatical errors, very unlikely characters, and insults to the reader's intelligence, but again, I still finished for some reason. I guess I was rooting for the author because I felt as if the book was something like I might achieve if I tried hard.