Everything I write here is my personal opinion and experience. in sharpness and HA it is much better than a similar Elka. very sharp in the open. "nuts" in bokeh start with aperture 2.8, in elka with 2.0 autofocus is tenacious, fast. Assembled very well. How whole. The fastening of the hood is reliable, dense. (by the way, at 135 2.0 the hood loosened in two years) after 2-3(?) years of use, still very satisfied. not going to sell. I shot it in the rain and in a snowstorm, there were cases of falls, a couple of times I put it on the asphalt and stepped on it (I weigh about a hundred). the lens went through fire water and copper pipes. there is no debris and dust inside, the sharpness is still on top. I recommend to everyone to buy, just check well for problems with af. my photos can be seen here: alexeyplatonov. Ru/gallery