I've had this lens for almost three years and I find it perfect for the task at hand: portraits of bugs and flies. You can use it for human portraits, but don't even think of this lens as a replacement for the 200mm f/2.8. Autofocus is terribly slow and noisy. The A850 2.0 firmware has somewhat improved this situation. When shooting macro, I usually use the lens in manual focus mode, so focus speed and noise aren't a factor. Thanks to the long focal length, I have a long working distance and…