I prefer watching NCIS: Los Angeles--it's more laidback, and the tech is better; those humongous giant screens they use in their op center are awesome.
Not really a fan of the franchise, but I started watching NCIS:LA after the crossover episodes with Hawaii Five-0 and found it okay. The great Linda Hunt is here, making sure that everyone stays in place, but the best reason that compelled me to watch NCIS:LA is the very hot Daniela Ruah, with her Nevus of Ota on her right eye and all.