I'm not kidding in the slightest when I say the new-style Butterfly mechanism on the MacBook Pro is my personal fastest thus far; that is, the somewhat deeper-travel one, not to be confused with the one on the paper-thin MacBook. Reliability aside (I did in fact have to get a top case swap under the extended warranty program), the short travel, the snappiness of the metal domes underneath, and the precise – if timbrally inconsistent – auditory feedback, really all come together to produce something that I'm faster on than even my Tactile Pro or my grey-badge Model M, by a good 20 WPM by my testing.