Plenty of work to be done - Hamilton
Lewis Hamilton admits there is still work to do despite leaving Jerez with their heads held high after accumulating more laps than any other team.
On Friday Hamilton and Nico Rosberg racked up 132 laps, bringing Mercedes' total for the week up to 309 overall. Despite not topping the time sheets in any session as of yet, the fact Mercedes has shown such reliability will give the team plenty of data ahead of Bahrain and is perhaps the most notable achievement of any team throughout the week.
Hamilton was full of optimism after the first week but admits there is still plenty of work to do to improve the car so that it can challenge the top of the time sheets in the upcoming Bahrain tests.
"The week has been fantastic, really fantastic," Hamilton said. "We didn't really make any improvements, the car has been the same since the beginning - but the amount of laps we got is encouraging.
"We are planning on being ready for the first race so I hope we are. I lost out a little bit in the last few days but every bit helps for the team and for me and Nico, so it was good to get back out there again today [Friday].
"We are not focusing on anyone else at the moment, only ourselves, trying to improve and get as much data as we can and as much miles as we can and try to take it one step at a time."
Opinions on the new cars have been mixed around the paddock, but Hamilton has joined the side of his old rival Fernando Alonso in saying there is not a great deal of difference between this season's cars and those from 2013.
"Its very similar, there's just less downforce," he said. "There's a slightly bigger workload, but it's just new - I'm enjoying it.
"Everything with starting the car is the same as last year, there's just a few little changes. Formula One is Formula One, so I don't have much [new] to say about it. The engines feel good, there's lots of power. It's a new challenge for everyone."