They seem to like it:
This has to be by far the most solid feeling Micro Four Thirds lens that we’ve ever handled. It feels every bit as solid and well constructed as a Leica lens would–and indeed it is co-branded with a Leica badge. However, it isn’t weather sealed so we need to keep that in mind when shooting.
It clearly looks like a great portrait lens for Micro Four Thirds cameras, and almost every reviewer is saying so. However, I find it a bit odd that this review doesn’t mention the Voigtlander 42.5mm f0.95 lens, which in my opinion is the closest competitor of the Nocticron.
Voigtlander lenses are famous for their tank-like build. They’re actually every bit as solid and well-built as the M-mount Voigtlander lenses for the full-frame Leica M system. I have held both lenses in my hand and, while the build quality of the Nocticron is exceptional, it’s still quite a while short of the Voigtlander.
Granted, it’s manual-focus only, but ignoring this lens in such a review feels somewhat wrong.