Americans - I Need Help Choosing A Bourbon

I've got a mate whos a big fan of Bourbon. He's tried all the standard brands like Buffalo Trace, JD, Jim Beam and Wild Turkey.

I want to get him a bottle for Xmas of something he might not have tried before, something I can say was recommended by Americans as a good bourbon. Doesn't need to be some weird flavour like Red Stag, just old fashioned American bourbon that maybe flies under the radar in other countries.