Fernando Alonso thinks that the new Ferrari is a "very strong" car, judging by its solid start to testing.
Although poor weather at Jerez in Spain this week has made it difficult to read much into the testing times, the good reliability the F10 has left Alonso upbeat about what Ferrari has delivered for this season.
"We keep concentrating on the laps – and the number of laps in these days makes the car very strong," said Alonso. "We've pushed some parts of the car to the limit in terms of mileage.
"So, we're happy with the car. We did a lot of laps in the wet on Wednesday and also in the dry so we're happy with that aspect and we'll continue working."
Alonso feels that car is providing good consistency over long stints, which was an area that he was focusing on this week.
Speaking about the different feel of the car over a stint, Alonso said: "It was different but, to be honest, with the degradation of the tires, the balance of the fuel – because every lap you have less and less – at the end of the day the car feels very similar every lap. You lose a bit of grip with the tires, but you gain a little bit with the fuel.
"It was a good test. We put the tires to the limit. We've been working very closely with Bridgestone to discover the limits of the tires for this year with heavy cars. It's very useful information.
"As always with tests, the priority is to have valid information for the races and I think today we had very good answers on some important things."
He added: "I think the car is feeling quite good, as we felt in Valencia. No big problems. For sure there are some setup possibilities to find a couple of tenths, but there will be time for that."