"We have a slight advantage over them in high speed sections," said Hamilton. "In slower corners they seem to be more agile.
"But I think the two cars are extremely close -- and that's fantastic," said the Briton.
Vettel agrees with Hamilton that the silver and red cars are closely matched.
"I'd say we have a good car in any situation but we've seen that they (Mercedes) are particularly strong in qualifying," said the German.
"In Australia I think we had a better car on race day -- we could see Lewis was struggling a little with his tyres," Vettel added.
And so ahead of the Chinese grand prix, F1 is in the new and quite unfamiliar situation of another race in which the outcome is basically completely unknown.
"It's been a while since battling with Lewis and it's a lot of fun to be back fighting him for poles and wins," he said.
"I also like this formula a lot in that you can drive on the limit in the race compared to how it was in the last few years. It's back to how it should be."
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