Many years ago, I played with both the Sigma 105 f/2.8 and the Tamron 90 f/2.8 and would have been happy with either. Ended up with the Tamron since it came up on a 2nd hand shelf in town before a Sigma did. More recently, I decided I could afford and justify (to myself, with the VR for non macro use being the deciding factor) a Nikkor 105 f/2.8. Keep an eye on the 2nd hand dealers' sites and see what comes up.