Quick sample shot with the TTArtisan 50mm f/1.4 shot @f/2 mounted on the Techart Pro AF Adapter and Sony A9:
Optically this lens is VERY modern. The way it renders, the contrast and colors just pop on a digital camera. OOF backgrounds at f/1.4 are CREAMY. Compared to my Nikon 50mm f/1.2 AI-S lens, it just wipes the floor versus that lens in regards to subtle creaminess (the Nikon 50mm f/1.2 AI-S has very fidgety bokeh). The center is sharp wide open especially at head shot and half length portrait photos. Build quality is just as good as any Voigtlander lens with smooth focus ring and hard click aperture stops. Barrel has a nice all-metal touch. Also I tried pointing the lens towards the sun, and it actually handles flare pretty well, unlike what other reviews have stated.
Saying that, I don't think I'll be keeping this lens. It's compact, but really heavy. It feels about the same weight as my Nikon 50mm f/1.2 AI-S with M-mount adapter attached and they're also about the same height w/adapter. The barrel is smaller, but it's a dense little lens. In regards to mid-field sharpness, this lens is best at centered focus shots. For full length portrait oriented shots, the mid-field is soft'ish when near or wide open. It also appears that way on Leica RF bodies from the Phillipreeve.net review, so I guess it's more of a design limitation based on the mount.
Since there are so many good modern 50mm lenses, I think I'd prefer something like the 7Artisans 50mm f/1.1 that is soft, but just gives you something different from all the modern 50mm lenses out there. If you're after a modern 50mm f/1.4 with excellent rendering, this lens is a good option. Saying that I'll probably just keep my Nikon 50mm f/1.2 AI-S due to it's faster aperture and more unique look despite not having nice OOF rendering.