>>4335351Agreed.
>>4335353M42 is nice for DSLR compatibility but adapters add a lot of length to mirrorless.
L39 with rf coupling would be nicer imo. Easily adapts to M mount as well as virtually any other mirrorless mount. Also works on old Leica screw mount cameras which are cheap as shit. I honestly feel like cheap modern Leica screw mount lenses are such an untapped market.