I'm not even half way through watching this show and I love it. The chemistry between Jane Fonda and Lily Tomlin is perfect. Plus, I really love seeing Martin Sheen back in a TV show. The switch from watching Sam Waterston on The Newsroom to this was nice. Overall, the main characters are enjoyable and I feel like this story is something that many older people may be able to relate to.
I thought this show was really good. What made it stand out was the format of the show, being played out in "real time." A few of the later seasons (not including the rebooted 9th season) were kind of repetitive to me, but what else do you expect with a show like this? It's a pretty simple plot: terrorists threaten the US, the FBI/CIA messes up and they call in Jack Bauer to save the day. Regardless of that, it was still pretty interesting and kept my attention.