It should be obvious really. I'll have a go at the top five, thus far:
1. Red Bull: Lots of cornering speed in all types of corners, excellent downforce in medium and high speed corners, excellent mechanical grip in slow corners, good traction but lacking straight line speed and worryingly clapped it's tyres out quickly in China despite looking fast initially when they were fresh. Setup issue? We'll see. They also seemed to have a paradox where they couldn't get their tyres up to pressure and temperature after pace car starts. Reliability - we'll see what drops out in the next three races as to whether they're on top of quality control.
Given the straight line speed of the Renault, you can't blame the engine for the lack of straight line speed either. I am also distrustful of their relationship with Renault. Renault have got it in the neck a few times from Red Bull when I don't think it's been justified, and no, I don't believe that if they had Mercedes engines then they'd be over the horizon as they say. 30 or 40 horsepower down on the Mercedes Christian? Not a chance.
Yes really, Red Bull have a few problems to solve even though I think we'll see the best of them at European tracks in normal dry conditions.
2. Ferrari: Good downforce, good cornering speed and seems to preserve its tyres well but their qualifying pace is not yet there, they're not as fast in races as they seemed in winter testing and their fuel consumption and engines are a worry. They're thirsty, having to turn down their engine revs to conserve fuel, possibly having to carry more fuel at the race start and they appear to be running rather hot. Reliability engine-wise is an issue.
3. McLaren: Excellent straight line speed and the system they have has given them a sizeable advantage to the tune of a handful of tenths in the races we've had (and yes, the grapevine says that's what it has given them). Cornering speed, downforce and mechanical grip, particularly in slow corners, isn't there, certainly in dry conditions and it's losing them what they're gaining on the straights.
I'm very distrustful of the bulbous nature of that rear end and have been since the car's launch. The duct system that that compromise is for has given them an advantage in many races so far, but I question what it's costing them in packaging and stability versus the Ferrari and Red Bull.
4. Mercedes: Puzzling, in a word. They don't look as bad as many thought, but the car simply appears to be average in just about every area, even in Rosberg's hands. Nothing you can say.
5. Renault: Brilliant job really. They've had question marks over the team's existence, but the developments they've managed to get on that car have been pretty impressive. They're still not where the top four are though.