See my Leica SL wishlist at B&H Photo.
I experienced consistent problems in the field with both autofocus and focus shift. Both issues are extremely serious in that they destroy image quality.
The 90mm findings incited me to disbelief, and wanting to disbelieve, I became curious if the issues also persist at 49mm with a $13K camera system. Well, field shots strongly suggested so, accordingly I confirmed:
Includes images from f/3.6 - f/11 including actual pixels. Well, all one can do is laugh. Go get a Nikon D810 and Nikon 24-70mm f/2.8E VR and forget about the SL practical joke. Or a Canon 5DS R and Canon 24-70mm f/2.8L II.
This study is at a reproduction ratio of 1:21 as determined my measuring the subject.