Do you think it's a worthwhile upgrade for those who have the 'old' non-VC version??
I definitely do, particularly since you get not only a slightly sharper macro lens, but also because you get a much more effective modern medium telephoto with a great stabilizer. The new lens does a lot of things really well and doubles as a great general purpose lens. I think its worth the upgrade, particularly if you can get a decent price on the used market for your old one.
Thanks, I may consider putting this lens in my upgrade path. I really like that the new version is non-extending. FWIW the image quality from the old macro is fabulous, not so much the looks of the thing...
I haven't used the old version myself, but your report confirms what pretty much everyone has said. I'm surprised the new lens hasn't had more buzz, but that may be because it was overpriced (particularly in Europe) on introduction. It is a very worthy lens, though, and a great choice now that the price is reasonable.
Because I hadn't used my 90mm macro for a while, and because I wanted to reconfirm the focal length and working distance on a full frame body (I'm selling my 7D), I took the lens to the zoo. 90 mm macro still works for me at least for butterflies, even on full frame but an image stabilizer would be very welcome.
I gave my 70-200+1.4 TC a go as well, but without a 1.6 crop factor the maximum magnification isn't quite sufficient for butterflies and such. That makes a good near focusing lens something I require more than before.
Hence, based on your review I'm strongly considering upgrading to the new version - for the convenience of the image stabilizer mostly. I'm sticking with Tamron for macro use, because as I mentioned before I don't do enough macro to justify an 'L' lens.
There's still nothing wrong with the image quality from the old lens, here's a few samples that I took today. Note that it was rather dark and the excellent high iso performance of the 5DMkIII is a real asset: