I wanna upgrade my camera D5200 to either a d7200 or D600 both are great cameras. I got my nikon 150-300mm and tamron 600mm to use. while the 7200 is faster the 600 is better quality in low light and that one is a full frame the other a dx. Who got what and how does it playout with bird photography. My 600mm tamron i can get the reach which i need.but not sure if it fits the 600 and the 7200 might just be in my favour at the moment.