I purchased this lens as a combination macro and portraiture lens. After ordering it, but before it arrived, I started to have second thoughts, worrying about how well it would perform as a portrait lens.
Well, I didn't need to worry. This lens is amazingly sharp and has great bokah.
In low light, it tends to hunt, but otherwise, focusing is reasonably fast. Excellent build quality, excellent feel when using manual focus.
I looked at the Canon 100mm macro, which is another excellent lens. However, the Canon would have required purchasing a hood (included with the Sigma), and the difference in price (around $160-170 with hood) didn't make sense to me.
No regrets! The images from this lens, both macro and portraits, blow me away!