Speed, performance, and feature wise, Firefox and Chrome are pretty equal (a few Ms off here and there for speed, a few rarely used Web standards, and different implementations of features are minor quibbling points). Where the differences are is the orgs behind the products. Google: For-profit organization that has been shown in the past not to respect user privacy, feeds much of what you do in Chrome back to their servers to adjust the types of ads you see in chrome, doesn't have your best interests or the internet's interests at heart, but only their profit. Mozilla: Non-Profit that not only respects user privacy (rated highest in privacy respecting organizations in 2012), but also tries to do what is best for users and the web. With no shares or stockholders, Mozilla is accountable to no-body but the user. Your data is always safe with us, and we always strive to make Firefox, and the web, the best they can be for you, not for advertisers.