I use this lens for a week now and could in this short period of time already testing some detail. But before I come to a short review, I will only explain my own expectations and requirements in short, I started (about 1 year) recently with photography. So when a student with more or less tight budget I prefer more the cheaper products and am now going to buy me little by a small pool of lenses and accessories together. As a camera, I use an Alpha 200 with the kit lens, a second-hand Sigma 75-300 APO I can even call my own. So now even a portrait prime lens was on my wish list. It quickly became apparent that the Sony blasts SAL50 F1.4 my financial capabilities, so I looked around for cheaper alternatives. Are often called then the "old" Minolta AF50 models 1.4 and 1.7. Is priced at least the latter in comparable scope with the SAL50 F1.8. So I had to decide between the two models. After I then but the current Sony could try the merchants, it was clear to me that Minolta would have no chance. Because - and I now come to my experience - the current Sony lens is just great. The autofocus works quickly and clean and was until now always correctly (no problems with back focus). In some test reports criticized that he was working too loudly. To my mind, I can confirm only partially. You can hear him, and you can hear him even more than the the kit lens, but I feel it is neither disturbing nor as a major shortcoming of the objective in general. Furthermore, the design of plastic is criticized (even the bayonet). I can recognize in no great disadvantage as well. So the objective is relatively easy held what I feel rather than beneficial. And who treats its equipment with care and with due care when changing lenses can exercise, which will have no difficulty with a plastic bayonets. We come to the optical power of the lens: Even though it is actually a portrait lens, I have primarily used until now for night shots. The focal length then prevents "tipping" of the photographed buildings and the great luminous intensity allows relatively short exposure times, which is better for the sensor (a tripod is still essential). Light dims (approx F2.8) achieves the lens - whether at night or for personal / portraits - class results. I have, apart from the standard zoom no direct comparison, but the fixed focal length beats the kit lens by far. And I am referring primarily to the subjective impression of looking at the pictures. Etc. Details such as vignetting, vignetting can be rather in the lab compare, so I allow myself to here no opinion.
Conclusion: Very good fixed focal length for those who need to make a little money on it. The "old" Minolta definitely superior and therefore above all an alternative for those who want to establish a used Minolta optics / wanted.