Nancy: This lens is deliciously sharp and trustworthy, I've used it on several occasions. Unfortunately I think the one I rented this time needs an adjustment or something. Several times throughout the day I had trouble with the focus. I kept my camera on One Shot, to focus and recompose, but the lens would behave as if I had it on AI Servo. It would refocus on the background randomly and without warning. I would rent it again if this issue is fixed.

Jason: Loved this lens! The bokeh was creamy smooth, the colors came out intense. I used it for a baseball game and a number of small concerts. The AF worked nicely and quite fast. It's a bit heavy for handheld for long periods of time, but the results are worth the extra fatigue.

Toothpick Ted: I've been doing model portraits and special event photography (both in the studio and outdoors) for a couple years now. I've mainly using fixed (prime) lenses to this point and had been seriously looking into this specific 70-200mm for my next "L-Series" lens to purchase. So I decided to sign up with B.L. and actually get my hands on the lens to give it run-thru. It totally met all the rave reviews and rants that I've been hearing about. The Image Stabilization is such a huge feature, especially if you're like me and tend to use things free-hand (without the tripod). The range of the telephoto is incredible and the lens is so quiet and fast (focusing, etc). I hope to soon add this lens to my arsenal. Until then, my recommendation is using BorrowLenses. I can't believe how easy it was to rent and I just picked it up/dropped it off at a local location to me. Great experience all the way around!!!

Tom: Wow ... I really did not want to return this lens! I rented the "Crack II" for a long weekend with no particular assignment - I just wanted to play with it a little. It was insanely amazing! In fading 8pm sunlight, soccer photos from about 200yards away handheld were sharp and steady enough to read the label on a moving ball! In a dimly lit club, handheld from across the room wide open at about 1/30 I can read the label on a microphone! No stage lighting, just a little help from lighted music stands. Wish the band members were a little less energetic ... the excellent image stabilization does nothing to steady a moving subject. The f2.8 does give you a fighting chance to use a much faster shutter speed than an f4 lens. Handheld shots of the moon and stars were pretty decent. The only drawback is the sheer size of the thing. It is a monster and weighs enough to make my neck and back very unhappy after carrying it around for a few days. Worth it, but a little unpleasant. Seriously - I want one of these to call my own! I just need to justify the $2400 or so ...

Danny: This is an incredible Lens. I rent this multiple times monthly for shooting weddings and events, and have been super-satisfied every time. It's fast, sharp, and has never given me a problem. It's a somewhat pricier rental than the original IS, but it seems a bit faster and I love what it produces. BL folks are always helpful as well. Thanks!

alibaba: I do a few surfing events every year and have been renting the canon 100-400 lens but this year I decided to go with 70-200 and a 2x extender and that was a great decision, it gave me the same zooming capability but the pictures even at fully extended to 400mm came sharp and colors looked vivid where with 100-400L lens you can't even get close to 400mm without getting a blurry smudged picture. This lens, without the extender is one of the best and sharpest lenses that you can find in any professional photographer's gear. Although this lens is very heavy and quite large and not a good lens to carry around, but the results will make you want to carry this monster around!

Julian: I rented this lens for an Airshow. This is a lens that has been on my list of "Must haves" since I got my camera. I was truly impressed with not only the crisp, clear photos this lens could produce, but also it's color reproduction. Just fantastic. I was pleasantly surprised by this lens, it met and far exceeded my expectations! I was shooting fast moving subjects and the IS provided that little extra bit of assurance that I was going to get the shots that I wanted. One thing to note, the size and weight of this lens should not be underestimated. I shot with this lens (hand held) for over 8 hours. At the end of the day, my arm was very tired, I would recommend using a monopod, or tripod for extended shooting. Overall, would 100% rent or purchase this lens!

WG Images: I would give this 6 stars if it were an option! We rented this lens for an arial photography project in low light conditions and it performed flawlessly. It performed so well that we rented it again, and continued the rental over 6 weeks. We were able to use it for action shots, portraits, street shots and a wedding. It is definitely heavy and you will feel the weight if you have to hold it long enough but the results are worth it. This lens is great on a 5DMkII. Combine this with the 24-70/f2.8L for a complete package.

Chad: The IS in this lens is amazing. Allows me to take pictures at 1/30 second at 200mm on a 7D. Far more sharp than it's older cousins, it's really worth the extra few bucks to rent this lens over the other versions.

Mark: Like others have said, I did not want to put this lens back in the box after using it. The autofocus is ridiculously fast and quiet. FYI, don't forget to check the focus search distance switch on the lens. Wasn't getting clear shots on a close subject and found out it was set to focus at a further distance. Contrast and color are outstanding. I used this for a wedding and several model shoots and this lens stayed on 90 percent of the time even though I had planned to use 3 other lenses that I rented/owned. Yes, it's heavy and I lugged it around for 10 hours one day. The thought of how great the pics were looking lessened the burden though. =) I also used a handstrap which made it possible to relax my grip and not have to squeeze the entire time, so my hands never got fatigued, just my biceps a little bit from the constant raising to eye level. I shot freehanded for every session and the IS helped virtually every shot look super sharp. Rent, rent, rent! Thank you, BL, for the chance to use an amazing lens that I otherwise would not have had the opportunity to experience. I will be ordering this bad boy again and again.