A DFA*50 F1.4 Hands-on, with Full Sample Photos

http://www.kennychi.com/lens-pentax-dfa-%e2%98%85-50mm-f1-4-sdm-aw-%e8%a9%95%e6%b8%ac/
(in Traditional Chinese)

With quite some samples, full original JPEGs available with EXIF at the linked Flickr. Some purple/green fringing can be seen at wide apertures, anyway.

Yet Another K-1 VS M2 IQ Comparison (Youtube)

https://youtu.be/JQKu972nvU8

I blog, you decide.

DPR has Re-shot Studio Scene

https://www.dpreview.com/articles/1423988259/letter-from-the-reviews-editor-pentax-k-1-mark-ii-studio-scene-re-shoot

Conclusion remains unchanged.

A Practical K-1 Vs Mark II Shootout (with Real Scenes)

http://blog.hisway306.jp/entry/2018/05/15/080000#K-1-Mark-II-vs-K-1-%E3%82%AC%E3%83%81%E3%83%B3%E3%82%B3%E5%AF%BE%E6%B1%BA
(in Japanese)

IMO, the images from the Mark II have dull colours as what DPR suggested. However, the resolution difference is not as huge, ditto for the noise difference.

K-1 II has Worse IQ than K-1 and is Not Recommended by DPR

https://www.dpreview.com/reviews/pentax-k-1-ii-review/11

I am not surprised with the conclusion for what I have inspected and found with different Mark II samples these days.

DPR K-1 II Samples are Out

https://www.dpreview.com/samples/5389645335/sample-gallery-pentax-k-1-ii

Same as what the PF has found, the direct out-of-the-camera JPEGs look soft to me.

DCW Reviewed the K-1 Mark II

https://www.digitalcameraworld.com/reviews/pentax-k-1-mark-ii-review

The K-1 is not compared, though. That is, the Mark II is assessed alone.

PF Compared the Noise/Details of the K-1 and Mark II

https://www.pentaxforums.com/articles/hands-on-reviews/k-1-ii-vs-k-1-noise-image-quality.html

"In JPEG mode the K-1 II has an edge, especially above ISO 12800.  At lower ISO settings, as we saw in the outdoor test, there is clearly less noise, but details are also slightly softer."

PB Reviewed the K-1 Mark II

http://www.photographyblog.com/reviews/pentax_k_1_mark_ii_review

The conclusion is well said. The upgrade is so subtle than it worths.

Another K-1 II New User Review

http://www.kennychi.com/pentax-k-1-mark-ii-%E9%96%8B%E7%AE%B1/

In Chinese, with samples.