Toro Rosso believes it has made good progress in preparation for its 2013 car in this week's test in Abu Dhabi.
Among other work, Toro Rosso has carried out aerodynamic measurements for its 2013 car, and chief engineer Laurent Mikes said the sessions have been extremely useful.
"The past three days have been very productive, as our car ran with no major problems. This allowed us to complete a lot of laps," said Mekies.
"Our job list was very full, testing many items, the majority aimed at next year's car, which will be very useful when it comes to preparing for 2013.
"In addition, it's fair to say that some of the work could be beneficial to us in the remaining two races of this year.
"Both Luiz, on the first and last days, and Johnny yesterday, did a good job for us, by not making any mistakes, thus allowing us to complete our programme."
GP2 Series runner-up Razia tested on Tuesday and Thursday, while Cecotto was in action on Wednesday.
The Brazilian driver managed to complete his programme for the day despite struggling with a high fever.
"It was tough for me today, although it didn't stop me completing the programme," Razia said.
"Like on Tuesday, the team had plenty of work for me to do and I was happy that I was able to find a good balance on the car and also had more confidence when it came to changing settings from the steering wheel while I was driving.
"Overall, these two days in the car have been a great experience for me and I really enjoyed working with an Italian team, as everyone at Toro Rosso made me feel very welcome."