If read as works of fiction, his books are very entertaining and I like them a lot. Just take anything he says with a grain of salt.
The thing that kills me is how some fail to credit the guy for what he has done.
I knew an instructor when I was going through Orlando who knew Marcinko and while he did say the guy had a major ego, he also said a lot of people give him a bad rap because he never toed the political lines and burned a lot of bridges during his time of service.