Probably the first 10 or so books.
I liked the puzzle components of the mysteries, and the writing itself is quite good. Sandford was a journalist, and it shows--his writing is crisp and brisk. He knows how to get your interest--and keep it. Every book is a pretty good page-turner type.
The cons? Well, I'll address the biggest one first: Lucas Davenport is a complete jerk. He's arrogant, self-serving and self-centered. He's not emotionally vulnerable and compassionate like Michael Connelly's Hieronymous "Harry" Bosch. Bosch is mission-oriented to a fault. When he breaks the rules, he does it because it's the only path he can see to solve the crime, so that he can bring justice to the victim--the justice is always his motivation. Davenport will break the rules because...well, because he can't stand to lose. He seems to want to get the bad guys to win, not for justice or the necessary peace of mind that closure would bring to the victim and loved ones. It makes him just about as criminal as the perpetrators he pursues.
IOW, to me, he's a pompous prick. I couldn't stand him after a while, so I quit reading.
The mysteries themselves can also be quite gory and sadistic, so brace yourself for that.
Of course, how i see things won't be the way others do. But that's what I took from the series.
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