Season 5 is so great. The Logan's, Aaron Pierce finally getting to shine, the opening episode blew me away when I first watched it, the CTU stuff in the middle with Samwise and Edgar, the ending is brutal. Still holds up so well despite the time premise being ridiculous at this point on the shows run.

The grittiness of the first season is still excellent stuff though, it's just the rest of it that is a muddle of excellent and awful parts