If Ferrari has yet to turn up their PU - arguably the best on the grid - I don't think we can make much of these times yet.
Mercedes has come back to Earth, a bit (relative to yesterday). McLaren looks quite quick but likely running a relatively higher PU setting than Ferrari.
Getting better rotation through low-speed corners would be nice, but I'd rather have a stable car that does well through medium/high-speed corners and treats its tires well, than a car that thrives in low-speed corners but is unstable, unpredictable, and devours its tires.