Well I always claim Alonso and Hamilton stand out from the rest because they'll drive the socks off anything. They both have the capability to put any car above where it belongs, be it a good or bad car. And they ALWAYS do it. They never give up. Kimi OTOH can certailnly do the same - but only when he feels like it. In 2006, for example, he underperformed vastly. True, the car wasn't the best but Kimi didn't exactly shine either.
Vettel we can leve out of this equation altogether. I've never seen him do anything extraordinary when the car wasn't a winning one - bar maybe Monza 2008. Although the Toro Rosso was obviously very good in the wet - I mean, even Bourdais was up there in qualy...
So I have to agree with Alonso here.
I think all of these four can win even if the car is not the best, they have all done it in the past and will do in the future as well.
I don't understand why you are saying Kimi didn't shine or perform well in 2006, he totally crushed his team mates Montoya and De La Rosa and sometimes outqualified Montoya over a second and he was thought to be very fast over one lap.2006 car wasn't good enough for wins.
Vettel can win even without the best car, he drove one of the most fantastic weekends with an midfield car and dominated tähe monza weekend, it's not his fault that RedBull since then have done great cars but even then he has won races were RBR hasn't been the best car
All of these four drivers are extremelly talented,fast drivers who are close to each other in every area, differences are minimal, Fernando is the most complete of them at the moment.