Bests & Worsts Reviews from Amazon

This was my first L lens and I am very pleased; zero buyer's regret for me. When I first started to seriously consider buying one of the 70-200mm lenses I wasn't sure which to buy. I first thought about buying the f/4 version because it was cheaper but then found out the f/2.8 comes with a case (~ $40), tripod ring (~ $120), and a hood (~ $35) in addition to the extra stop in aperture. For the $600 difference it reduces down by about $200 by including additional stuff that you, frankly, should have. Most notably is the tripod ring which takes the lens weight off the camera body but also balances the camera at the tripod mount. With the f/2.8 attached to my 300D it balances just fine on the tripod foot (even with a EX550 flash). In shooting with a tripod it's very easy to rotate the lens within the ring to go from landscape to portrait without off-balancing the weight. The extra weight is an issue depending on your muscular build. I can shoot for a couple hours without the weight being bothersome but my fiancee (very petite) has some difficulties. In actual shooting I find the tripod ring comes in handy to put the weight on my palm thus leaving my fingers free to adjust zoom and focus without a hassle while providing a firmer base for stability. I cannot comment on the f/2.8 IS version since I've never used it but I have seen people selling their f/2.8 IS because it was too heavy. All-in-all this is an extremely good lens and you get exactly what you pay for: quality. Some day I intend on complementing this lens with the 24-70 f/2.8L for wider angle shots. Of course, if you have the chance to test all three versions of the 70-200mm lens at a store then you certainly should test them for yourself. And, by all means, buy a UV/protector lens.