Ferrari protegee Raffaele Marciello says this year's SF15-T is a definite improvement on last year's car.
The GP2 driver, a member of the Ferrari academy, had his first taste of this year's car at the Barcelona circuit on Tuesday.
Behind the wheel on Day One of the Spanish test, he covered 125 laps while working on aerodynamic development for the Scuderia.
His best time, a 1:26.648, put him third on the day's timesheets.
Tuesday's run was Marciello's first in the 2015 car having last tested for Ferrari back in the Abu Dhabi in 2014 and he reckons the progress is clear.
"Even though it's the first time I have driven this car, I got positive feelings from it," said the Italian.
"I think the team has done a good job: the last time I did a test, it was in Abu Dhabi last year and there's definitely been a lot of progress made since then.
"We will now analyse the large quantity of data we gathered on the new aerodynamic package used last Sunday to further improve our performance."