Lewis Hamilton - 3rd: "It was a very good session and a positive day for me. In P2, I think some debris from one of the incidents must have caused my puncture because I'd only just left the pits when I suddenly felt the rear sliding about.
"Nevertheless, we got through a lot of test components. I'm still trying to find the exact balance I need, and I'm not quite sure which direction I want to follow with my car, so I'll sit down with my engineers to analyse the data this evening.
"Our long-run pace is pretty good; the speed is there. It looks very close once again between Red Bull, Ferrari and ourselves, so we'll work on qualifying, get the car nicely dialled in and then I'll keep my fingers crossed.
"It's surprising to see so many incidents here, but it's such a demanding and slippery circuit that I guess some people just got caught out today. We're all testing the limits of our cars and you can't blame people for trying. There's no room for mistakes around a place like this and, unfortunately, some people paid the price today - but they'll bounce back tomorrow."
Jenson Button - 4h: "It's very difficult to make effective set-up changes when there are so many red flag stoppages. It's a very tough circuit here - one hit of a kerb in the wrong way can send you into the wall.
"But we did some high-fuel runs on the Option tyre; it was key to get some laps on the Supersoft. It's all useful information and I'm confident we can still improve the car's balance on low-fuel.
"We didn't do any low-fuel running on the Supersoft because of the two red flags, so we just filled the car up and sent it out at the end of the afternoon. It's pleasing that the car felt pretty good on high-fuel.
"The Red Bulls are quick, so are the Ferraris, the Mercedes and ourselves - I think it'll be a little bit closer than it's been in the past few races."
Martin Whitmarsh - Team principal, Vodafone McLaren Mercedes: "Today's sessions showed how unforgiving this circuit can be: you only need to get the car slightly off-line, or hit a kerb at the wrong angle, and you can end up in the wall. Happily, all the drivers emerged unscathed, and the marshals did a fantastically efficient job of clearing the track and sweeping away all the debris.
"Despite the unusual number of stoppages, we still managed to make some positive progress, evaluating a number of minor modifications we'd introduced for this race and carrying out our tyre comparison programme - albeit with some disruption owing to the red flags.
"Both Lewis and Jenson are pretty happy with the balance of their cars, although there's still some work to be done to improve the set-up. As usual, the competition looks evenly matched - particularly so this weekend - but the unpredictability of the weather and the unforgiving nature of this circuit all look set to make for another close race."