My friend has a 100mm macro and LOVES it for portraits. I have never tried it myself but the camera store in the next town is pretty nice when I visit there as they let me try their lenses for sale on my camera, so I might try a few out sometime.
I have a Sigma 70-200 f/2.8 OS (stabilization) and it seems pretty close to it’s Canon counterpart, though Canon’s has a much closer minimum focusing distance which is useful in some situations. But the Sigma is several hundred less in price. My next lens will probably be the 24-70 f/2.8. I have rented it before for a wedding but I don’t typically do weddings. But I do want a wide zoom.