It's a beauty of a lens, but not better than the 42.5/1.7. It does have a special look for portraits, no question.
AF Speed
Olympus 45mm F1.8 vs Nikon 32mm F1.2 IQ
http://bigstreetguns.com/2017/03/olympus-45mm-f1-8-vs-nikon-32mm-f1-2-image-quality-comparison/
Great price for such a good lens. I paid way more.
M. Zuiko Digital ED 45mm f1.8 (Black), $239
http://www.getolympus.com/us/en/outlet/m-zuiko-digital-ed-45mm-f1-8-black-reconditioned.html
Measurements
https://www.lensrentals.com/blog/2018/03/finally-some-more-m43-mtf-testing-are-the-40s-fabulous/
Even though I have tested the 45 against the budget Lumix 42.5 countless times, and I'm aware that the Olly has some features--color, rendering--that make it a good choice for filming a "portrait", for example a solo violin, flute or singer, I always reach for the 42.5.
That's a deal!
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