Canon EF 100-400mm f/4.5-5.6L IS USM

alibaba: This is a big, heavy lens with an old school pull-push zoom mechanism. I rented this for a day at the beach taking pictures of surfers, and found that it's not the sharpest lens but with any lens with this range of zoom you don't expect the best quality. If you rent this lens, you should definitely stay away from 400mm range as you loose quality noticeably, 300mm would be your best bet. Using the pull-push zoom was interesting and easy. the friction ring is very helpful. the IS works great. This is a heavy lens so make sure you at least rent a monopod or tell your arms goodbye as they'll be toasted if you use it handheld.

Jason: Excellent lens, great build. It may have just been my choice of backgrounds as I was shooting, but I found the bokeh on this was not as smooth as some of the other Canon glass I've used. Shot the NCAA Div I Football Finals game with this in January (handheld!), as well as using it on a road trip. Great clarity, fast enough for full daylight levels, but found it a touch too slow for a night football game, even with the large amount of lighting. The push-pull zoom takes a little getting used to, but once you figure it out, it is very convenient. I loved the ability to lock it at a certain focal length. I would not recommending going handheld for long periods of time unless you can't take a mono/tripod with you (many stadiums don't allow them).

Charles: Amazing lens for soccer photography. The lens might seem a bit 'slow' at f4.5-5.6, but at least under the lighting conditions I was shooting under (evening, sunny summer day), it was more than fast enough The push-pull zoom takes a bit of getting used to I also found the lens very contrasty, which is a good thing.