Rumours are worthless. Maybe Virgin have been running with 200 Kg ballast also?Some rumors are saying that Red Bull has been driving so far pretty much only with full tanks, meaning they would be leaps and bounds faster than anyone else
Why would you only test with full tanks? How does that help you set up the car wrt. quali? How can they run with full tanks in the long stints they have been doing? Remember Webber did 139 laps in one of the testing days. That is hard to do if he had to come in to the pits to top up all the time.
I call bullshit. RB7 is going to be quick, though.