Pros: Size matters, but in the spy world it’s the opposite - short and thick is hot. Takes great pictures ranging from 70–300mm. I was at a crowded 4th of July event and didn’t have to worry about bumping into people with a long lens. No dust go in while shooting a demolition derby. Captured fireworks without any trouble. 1080p video from my T1i is very sharp considering the focal length I was shooting. Hood & soft case included, btw, don’t buy one.

Cons: The zoom ring is stiff at first but after a day of shooting it will loosen up, as will your hand. I feel the ring is a bit narrow, but what do you expect for a compact lens?

Other Thoughts: I’ve heard complains of chromatic aberration but I haven’t witnessed any, even in bright, backlit shots. Reviewed photos on 32” LCD – still didn’t see any.

Pros: Size matters, but in the spy world it’s the opposite - short and thick is hot. Takes great pictures ranging from 70–300mm. I was at a crowded 4th of July event and didn’t have to worry about bumping into people with a long lens. No dust go in while shooting a demolition derby. Captured fireworks without any trouble. 1080p video from my T1i is very sharp considering the focal length I was shooting. Hood & soft case included, btw, don’t buy one.

Cons: The zoom ring is stiff at first but after a day of shooting it will loosen up, as will your hand. I feel the ring is a bit narrow, but what do you expect for a compact lens?

Other Thoughts: I’ve heard complains of chromatic aberration but I haven’t witnessed any, even in bright, backlit shots. Reviewed photos on 32” LCD – still didn’t see any.

Pros: The size of this lens is a really big help in its use. Much easier to use than my previous 100-300. The Image Stabalization is the best feature of this lens. Was using the lens at full zoom (300mm) on my Canon EOS Digital Rebel XTI taking pix at the zoo. With the 1.6 factor of the camera, the lens was at an effective focal length of 480mm. As I tried to photograph a lion I could not hold the camera still enough for a good picture. When I pushed the release half way all of a sudden the image in the viewfinder became rock steady. I have downloaded the photo and the sharpness is amazing. You could count each hare on the lion's head. No way I could have done this without IS. Also, the focus is incredibly fast, and as with my other USM lenses, virtually noiseless.

Cons: The zoom ring is very stiff. The lens has a zoom lock so it will not extend when transported face down. This lens zoom is so stiff it can't extend on it's own.

Other Thoughts: This is a fantastic lens. The relatively small size made possible by the Difractive Optics is more helpful than most people realize. Once you use it you will appreciate this feature. While not cheap by any standard, I am glad I bought it and feel I got more than my money's worth.