I'll preface this by saying: for Scotch I consider Laphroaig 10, Balvenie DoubleWood, Highland Park 12, and Talisker 10 to be essential to any enthusiast's collection.

What do you consider to be essentials to a quality bourbon selection?

I'm fairly new to bourbon (while not impressive, my current arsenal includes Wild Turkey 101 [a real humdinger!], Buffalo Trace [uninteresting], Knob Creek [okay], Old Weller Antique 107 [haven't opened], but that doesn't mean I don't like delving right into the more complex/challenging stuff (heck, the first single malt I bought was Laphroaig 10, without ever trying it, and loved it), so let's not let that affect your input.

Thanks gang!
Jeff