Top F1 drivers should not "judge" Formula E before trying it.
That is the view of Andre Lotterer, a multiple Le Mans winner who even did a race for Caterham in 2014.
"We have incredible acceleration from the electric motor," the German told Kolner Express newspaper.
"We do not need the huge downforce that they have in Formula 1 so we can fight better, and Formula E is much cheaper," Lotterer added.
"We also drive on exciting tracks in metropolises like Paris, Rome and Berlin. Every race here is Monaco.
"Hamilton and Vettel should give it a try before they judge," he said.