Get Leica 28mm f/1.4 Summilux-M ASPH at B&H Photo.
This series is a counterpoint to the Church at Night series, which showed a real headache from field curvature. In this series, it is show how careful choice of focus to balance field curvature against the shape of the subject can result in much higher image quality.
Includes images up to full camera resolution from f/1.4 through f/8.
BTW, what a nuisance with the Leica M240: its EVF crops just slightly and asymmetrically, so a scene like this requires trial and error to center the image properly.