I think the cooking rule of "don't use it if you don't drink/like it" applies to any liquid addition to your brew.
Coffee, honey, wine, bourbon, liqueures, etc. etc. etc.
While I agree that I wouldn't cook/brew with something I don't enjoy, there is definitely a point where you're wasting the good stuff. You're not going to be able to pick out the nuances that separate a $100-a-bottle whiskey from a $30-a-bottle whiskey when added in reasonable levels to a batch of beer.
I like to add Scotch to my beef stew, but you can bet I'm using my 12-year old Balvenie, and not my 21-year old.