I like mild because I drink coffee almost exclusively as my only liquid intake and I have it in my cup all day, during every waking hour. Doesn't keep me awake anymore, I sleep fine. I just like the warm smooth flavor, and combined with some milk and sugar, tastes good, and helps sooth a bit of heartburn I tend to have in my older years now.
Yay coffee! And especially Costa Rican coffee. I'm voting with your wife on this one.