The answer? American.

That's not to say that Russian aircraft cannot compete at all, which they certainly can, and in certain areas they could achieve superiority.

The U.S has not had to overcome a total collapse of its economic and military systems, unlike the Russians - who are only fairly recently beginning to step up their game with technology.

Although your choice is yours entirely. To know more about the two aircrafts, watch this funny comparison of American and Russian Jets. Enjoy!