The reigning world champion believes his team will be better prepared for its latest title defence after a relatively smooth start to its running with the RB9.
Asked how his feelings compared to the same point in 2012, Vettel replied: "A little bit better, because I think last year we had some issues with the reliability.
"It seems that we've done our homework well.
"I don't think we can really say anything about the performance yet."
Vettel suspects the forthcoming Barcelona tests will reveal more about the cars' pace, though he doubts any real conclusions can be drawn before the first race.
"People run more and probably start playing around more [at Barcelona], so I think if you keep your eyes open, you might start to understand things a little better there," he said.
"But at the moment we're focusing on ourselves and understanding our car.
"Surely within the next two tests we'll know a little bit more both about ourselves and about the others, but then again Australia is a very different track with different conditions.
"I reckon Barcelona is going to be a little bit cooler here and cooler than Australia so it might be difficult to get a heads-up before the start of the season."