I finally got to try some Vittoria Pistas on the rollers. They rolled dead even with the Corsa Speeds, literally watt for watt on the rollers, which suggests if there is a difference on the road, it's well under a watt. That was surprising, given the differences:
* Pista is significantly lighter at 180 grams (vs. 240)
* The Pista tread feels a bit thinner
* The Pista tread is a little different - the center is slightly textured. There are slight grooves on one side of the center -- versus both sides on the Corsa speed. Presumably you're supposed to mount the tire according to the direction you go around the track -- though it's not clear to me if the grooves go on the inside or the outside.
* The Pista was indeed easier to mount on a wide rim.
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