I'll admit, I really enjoy TFA. I saw a little preview of it at Comic-Con last year, and I was certainly intrigued by the style of the characters. As Medikor said, there's a great cast of characters: David Kaye (Optimus Prime and Lugnut), Corey Burton (Megatron and Ratchet), Tara Strong (Sari), Tom Kenny (Starscream and Isaac Sumdac), Jeff Bennett (Prowl), Bumper Robinson (Bumblebee and Blitzwing), and Bill Fagerbakke (Bulkhead). There are also a few others worth mentioning that don't appear as much...Phil LaMarr (Jazz), Townsend Coleman (Sentinel Prime [did Michaelangelo in TMNT in the 80s-90s, and The Tick]), and musician "Weird Al" Yankovic (Wreck-Gar) appeared in a recent episode.
It can be a bit of a lighthearted series, but there are darker moments around.