BBC F1 technical analyst Gary Anderson and I watched at various points around the track on Tuesday, and while it's impossible to see which car is going to be a winner just from observing, certain aspects of the cars' behaviour are instructive.
The Lotus looks nimble in the hands of Romain Grosjean, while the Red Bull of Mark Webber appeared to be running on a heavy fuel load in these early sessions, the car reacting more slowly on turn-in and acceleration than when light of fuel.
The Toro Rosso of Daniel Ricciardo looked promising in the slower corners, as the back of the car looks responsive to his inputs, while Paul di Resta was silky smooth and consistent in the Force India. The car appears to turn in well, it rides over kerbs and bumps with minimal deflection and he set a competitive time with absolutely no drama.
This circuit at Jerez is not typical of many current F1 tracks, and a car that is fast here may not necessarily be on the pace elsewhere, but it can still give clues.
We came across 1982 world champion Keke Rosberg - Nico's father - watching from one of the final corners, and he wasn't too impressed with the Ferrari of Felipe Massa, and thought that Pastor Maldonado was a bit ragged while pushing hard. That made Gary and me smile, as the Finn was well known for his hard-charging technique.
Maldonado's car is in fact the 2012 version with some updates, and Williams are the only team not to have unveiled their new car as yet. Perhaps this explains the Venezuelan's abandon - he may well feel a little less sense of responsibility than drivers who are out in the brand new cars, for which spare parts will be at a premium.