Hi, just want to add that some mods to make those lenses work on a DSLR , Nex or MFT not only augment the focal length, but also lower the effective speed of the lens ( these mods work like teleconverters ), so I don't see the point....
While I never owned the Canon 0.95, it seems to be a good choice, prices are still reasonable compared to superfast Leica Noctiluxes.
Be aware that DOF becomes extremely thin at such apertures, a high percentage of shots are crap due to focus errors resp. subject movement.
My Schneider Xenon 50mm from 1967 works fine on a Nex, but would vignette somewhat on a FF camera.
Got mine for ca $1000, but have seen auctions going up to $2500 +