Review: "Sigma has a reputation of producing good lenses at low prices, but with the advent of some of their newer, more expensive optics, they're extending that game plan to the production of very high-quality optics at "reasonable" prices. This 150mm f/2.8 macro lens is an example of this, knock-your-socks off optical performance, good build quality, and a quick AF motor.
At the end of the day, the Sigma 150mm f/2.8 macro seems to offer the best bang of just about anything in its focal length/aperture range. If you're interested in shooting really close-up macro, yet with a reasonable working range, the Sigma 150mm f/2.8 looks to be a really excellent choice."