Pirelli motorsport director Paul Hembery has revealed that teams were all 'very positive' after getting their first taste of the 2013 tyres in practice on Friday in Brazil.

The Italian firm brought two extra sets of prototype tyres to Interlagos, in addition to the usual hard and medium compounds which have been nominated for the final round in the 2012 F1 World Championship, and they were mainly used in the first practice session, although Daniel Ricciardo, Vitaly Petrov and both HRTS also used them briefly at the start of the second session as well.

"With testing opportunities so limited in F1, we wanted to give teams the opportunity to try out our [2013] tyres before the first official test in February next year, so that they can start to understand how the new tyres interact with the current cars," Hembery explained.

"The initial feedback we received has been very positive: the tyre that the teams tried today has a different structure with a faster warm-up. This delivers extra performance within a wider working range, due to increased cornering grip, which is exactly what we were aiming for.

"When we combine the new structure with the new compounds for next year we will see the full performance potential."

So what did the drivers' think of them?

"We only ran a little with the 2013 tyres in the morning," said Lotus driver, Romain Grosjean. "My initial impression is that they feel a bit better and you can notice they have a different construction."

"It was interesting to get a taste for them and do a direct comparison with this year's tyres," added Force India's Nico Hulkenberg.

Toro Rosso pair Jean-Eric Vergne and Daniel Ricciardo echoed those thoughts: "We had some 2013 tyres to try today and we had some sensors fitted this morning to see what they did. It's interesting to see for next year as the shape of the tyre is slightly different which will have an impact on the aero," Vergne noted.

"They felt a little bit different, but nothing dramatic," was Ricciardo's take. "Let's say we didn't find any negatives with them...."

The team bosses meanwhile all felt that the chance to use the prototype tyres was beneficial: "The decision to provide each team with 2013-spec Pirelli rubber was extremely useful. Many teams, ourselves included, took full advantage of the opportunity to measure and understand the new tyres' behaviour ahead of their introduction next year," said McLaren team boss, Martin Whitmarsh.

"Romain completed some interesting back-to-back comparison runs with Pirelli's 2013 development tyre which looks to be a few tenths quicker than the current configuration even on this year's car," remarked Alan Permane, Lotus's trackside operations director.

"It was interesting to have both drivers run the 2013 tyres that Pirelli supplied to all the teams here," summed-up STR chief engineer, Laurent Mekies. "We got some useful data for next year, therefore it was important to invest some of our track time in this exercise."