I put in a Sony with a USB input about ten months ago. The other day the wife asks if she can play her new CD. I gave her a stupid look and replied "I forgot it even had a CD player".
Seriously though, I have a 16gb micro-SD card in a tiny little adapter with over 300 songs on it, and it's not even close to being full yet. Everything from Johnny Cash to Tom Waits, Van Halen to Horropops. Lately I'm on a Rockabilly kick. I never even set the radio stations from the last time the battery was disconnected about a month ago. Now I'm spoiled and refuse to tolerate all the idiotic car commercials.
Old country.. depends on the artist. New country, not in my Jeep, ever.