Now that T-Mobile and AT&T don’t have to pretend to like each other anymore, the nation’s No.4 carrier can go back to attacking AT&T and its top-selling smartphone, Apple’s iPhone 4S. T-Mobile debuted a new TV commercial this week that once again takes aim at AT&T’s slow network and Apple’s popular iPhone. “If this is the speed of the iPhone 4S on AT&T, what does 4G speed on T-Mobile look like?” the ad’s narrator asks as a man cruises along the highway on a motorcycle. Then, T-Mobile’s TV spokeswoman flies by the man while decked in leather on her new motorcycle. T-Mobile might be going out of its way to draw attention to the fact that Apple’s iPhone will be supported on its network by the end of the year but in the meantime, expect plenty more ads taking shots at Apple’s handset and its top U.S. carrier partner. The full video can be viewed below.