I had to google "daily driver" and this was the first definition: A bong that is mainly intended for everyday use.
But if you meant, what's your day-to-day bourbon, I'm still feel semi-new at the bourbon game so I'm still trying to experiment and taste all of them. I usually have a high-end bottle and a sub-$40 bottle going.
And while they do vary as I try new stuff, I do often fall back on Elijah Craig, Ol Grand Dad 114 (a great value for a strong whiskey), Wild Turkey 101, and Eagle Rare 10 Yr. If I'm really limited in selection, Bulleitt bourbon will do too.