Hamilton says he is "in a good place" but Sebastian Vettel complains of a "loss of grip" following their first experiences driving their 2012-spec cars on the third day of pre-season testing in Jerez.
Hamilton states "things went pretty smoothly" and had "no nasty surprises" after driving his new McLaren MP4-27 for the first time.
By contrast, Vettel reveals he is struggling with his new Red Bull RB8, complaining of "quite a big loss of grip" compared to last year's car which was built around the now-illegal 'blown diffuser' exhaust system.
The double world champion, who will be chasing his third straight title, says he is having to adapt his driving style to cope with the changes.
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