Much has been written about the advantages and disadvantages, so I want to say about the main thing for me personally - about reliability. The lens has a very delicate construction due to the moving part. There was a sliding fall of a camera with a lens from a height of 30 cm in a lowepro closed soft bag. After that, the focus jammed. After 15 minutes, we managed to "unwedge" it, gently deflecting the moving part of the lens first to one side, then to the other, and turning the focus ring.