Although Nico Rosberg reckons Merc's pre-season was "better than expected", the German is refusing to make any predictions ahead of Australia.
Following the last pre-season outing in Bahrain, Mercedes and Williams emerged as the teams to beat - at least on paper.
The two teams not only dominated the timesheets, taking the top four positions, but they also had some of the better reliability.
Mercedes, though, did run into a few problems in the final test but still finished fourth on the log for most laps covered.
The team returned to Brackley for a few days before heading down to Melbourne where Rosberg says he is eager to see just where Merc are in the pecking order.
"This year, after completing the final test in Bahrain, I returned to the factory at Brackley for the final preparations in the simulator and went straight on to Melbourne from there," said 28-year-old.
"Overall, I think our winter testing programme went better than expected.
"Having said that, the first grand prix is the first real opportunity to judge how well we have done against our competition. Pre-season doesn't tell the full story, especially this year with the new regulations.
"I'm really looking forward to getting the season underway and can't wait to be back in the car again."