I've read several Virgil Flowers novels. I don't see Sandford as being blatantly anti gun, anti-American, or even anti Christianity. Sandford writes Flowers' character as if he (Flowers) is enlightened beyond such mundane things. Flowers is represented as a fishing fanatic and roots rock cognoscenti. He has a gun but it's usually in the car when he needs it, but that's OK because he has a first rate mind and lot's of friends everywhere to take care of him.
The rest of Sandford's characters, including Flowers' girlfriend are less refined and more normal.
It's fiction. Oftentimes the writing is humerous.
The biggest detraction I see is that if you've read one, you've pretty much read them all.
