Same here.

Strangely, I like my biopace on my Pista, and I like my round, steel Surly ring on my Karate Monkey.

Other than the fixed gear and clipless pedals, it has taken me almost three years to find the right stem for my bullhorns.

But then...everything.

Each piece of the puzzle that has improved the fit and function has increased my joy in riding beyond any rational expectation.

Finding a seat post with a 35mm setback changed my life.

Discovering the combination of a Conti 4 Season tire in front and an Armadillo in back changed my life.

Brooks saddle.

Barend brake lever.

Cane Creek Volos Track wheels.

But I guess if I had to pick one thing, I would pick four; bullhorns, stem, setback seatpost and saddle.