Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Less than O.K.

This is a well built lens with less than ideal performance. From time to time it will surprise you with an acceptible picture (close to very good) but never great. With bright light, a tripod and a frozen bird you may get a great picture. I will continue to use and study this lens but it will not be my primary 300mm telephoto. The Canon IS 300mm will be in my bag. It's o.k. to use this lens to learn camera and lens technique and develope good photography habits. But if you can afford the Canon 70mm-300mm with IS get that instead.Update: After using this lens for several months now, I would like adjust my previous rating of this lens. Perhaps I have developed better lens and camera habits and techniques..... you think. My pictures quality has drasticly improved with this lens. If this lens had IS or VC I would rate a 5 star. As it, I'll go with 4 stars.