Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Flawless!

I thought my K20D was only so-so until I got this lens, now any mediocre images I get are my fault (but still crisp). Focus quick & quiet, depth of field entirely under my control if I use aperture priority. It seems heavy when I'm carrying it, but balances nicely in the hands when shooting. Never owned a lens this good before.