I've got (what I think is) a quality collection. My prize pieces are my SG King Stemline, my Luke Wilson 15 Arm, Ben Wilson Mini Inline w Triple Donut, and my traveler Headford Jacuzzi Bubbler. Plus, I've got a few dry pieces from over the years, and a few LHS bongs. The thing is, I feel like I'm missing a piece to kind of finish the collection (for now). Any suggestions on a must have piece? I recently bought a few of these pieces, so I'm in no rush, but the right piece would force my hand a little.