I bought 10x50 Bresser Porro on sale. It is a good pair of binocular, very sharp, clear image. You can see details of the birds close and long range.
I was so impressed I bought another 4 pairs for each of my family. I was happy with them for about 2 months. After 2 months of daily usage, my pair was out of focus and every object I looked at was double vision. There was nothing I could do to get rid of the double vision. I thought this was a one-off. However, the following weekend, I checked my mother's pair and this, too, show double visions after very little usage. 2 out of 5 pairs that I bought are out of focus, so far. I am dreading that the rest of the 3 pairs we have will go the same way.
Although the quality of the image is wonderful, I am disappointed that they do not last long.