Ok, how about the Canon 70-200mm f/4 IS. I know it's a little bit out of your buget, but it is extrmely sharp, and the IS allows you to hand hold about 4 stops slower shutter speed, has great AF, slightly better than the non-IS version, weather sealing,you will only cry one with that lens. Look at Bryan's ISO 112233 crops, it hasincredible sharpness. If you really want get out on a limb, check out the Canon 70-200mm f2.8 IS, for portriats it's awesome.