Ya, I just realized the Tammy was the 85, see above edit...The Tamron is a focal length I'll use more often, and the size/weight/VC make it more user friendly, but the Sigma seems like a winner as well. Both are plenty sharp, have low longitudinal CA, focus quickly and accurately, and render to my liking.
True, it's been mentioned on the MU-43 often enough that that Sigma was very much involved in the making/ construction of the Oly 75.reminds me of an FF version of the Olympus 75mm 1.8! If rumors are true, the Sigma 135mm 1.8 Art shares a little optical DNA with that lens as well!
Thanks, not the time to bin the 75 just yet then (I don't think I ever will).They are both very sharp, render neutral bokeh, and focus quickly. The rendering is different - the Sigma has slightly swirly bokeh whereas the Olympus stays round with a bit of cat's eye in the corners. Also, the out of focus transition of the Sigma is very abrupt. It can look like a subject has been cut out and pasted onto a background.