The Su-27 is an indigenous Soviet design, and is worthy of respect, if for no other reason than the fact that the Soviet engineers managed to create a craft with near-US-fighter capabilities (the Su-27 is probably the world's most agile aircraft, despite being damn big, google Pugachev's Cobra) using 1950s technology. The Chinese picked a good base to start from, but as they lack the massive aerospace program the Soviets built, they will have a hard time improving much on the design anytime soon. That being said, this thing is SO raptorbait.