I just compared the following lenses on a similar subject : Porst 55/1.2, Canon FL 55/1.2, Rokkor MC 50/1.5, Rookor MD 50/1.7, Rollei 50/1.8 Planar, Canon FD 50/1.8. Best overall sharpness/contrast goes this way : Sharpness : very slight edge to Rokkor MC 1.4 (@F2) against FD 1.8 @1.8. 3rd place, FL55 @ 1.5. Rollei #1.8, MD @1.7, Porst @F2. Contrast : tie between FD 1.8 and MD 1.7. FL55, MC1.4 on par. Slightly under : Rollei and Porst. Bokeh : winner Porst (pretty soft all over, so this is the silver lining), FL55, FD1.8, MC1.4 and Rollei tie, last MD 1.7. Pleasure of use : tie FL55 and MC1.4. Then Porst, and MD 1.7 (tie on the sheer dampening, but build feeling much nicer on Porst). Lasts, Rollei (focus ring ever so slightly stiff) and FD (horrible cheapo plastic all over, though well dampened focusing ring). Compactness : MD1.7, FD1.8, Rollei1.8 Planar, Porst 1.2 and MC1.4 nearly tie, last, Big Boy FL55. Value : Canon FD 1.8 absolute best bang for the bug nifty. If you can live with the plasticky feel and zero bragging rights or coolness factor, it's probably one of the best 50's you can get for your NEX. Plus, it's small, light, and cheap. Difficult to pull the others apart depending on how much one pays for them. I'm having huge second thoughts about selling the FL, it's one hell of a fine lens. The Rollei is a suprisingly nice lens all around, beautifully balanced between sharpness and bokeh, strong build, good size and looks, I'd just wish a slightly more buttery smooth ring (might be sample related though). I think if I could keep only one I'd chose between the FL55 and MC1.4, but that'd be damn hard to do !!