Excerpt: It was a used purchase, but I couldn't tell it isn't new. I'm still learning a lot, but this made it much easier to get good, indoor basketball pictures with the right combination of ISO given a 2.8 aperature. It doesn't focus as I think it should, but an on/off of the camera seems to correct everything. I wish I had splurged for an AV model, but I'll get used to it for a price of about $550.
Summary: I have taken some good images with this lens. Sometimes it just feels slightly flimsy, mainly when shifting between auto and manual focus. Sometimes this transition feels imprecise, as though there is a little too much free play in the plastic focus ring. I have used it outdoors and at indoor (red carpet) events and it has performed quite well in both auto and manual focus. The images were sharp suggesting good quality glass.
Excerpt: This is my first Non-Nikon lens and one of 2 zoom lenses I own (the other being the 14-24). I decided against the Nikon version because of price difference and because I don't do weddings, this would be strictly a 'fun' lens for me. I was a little skeptical at first, I'm kind of a Nikon snob, but so far it's impressed me. I haven't had any problem getting sharp focus and it's pretty quiet too.
Pros: Consistent Output, Durable, Fast / accurate auto-focus, Nice Bokeh, Rugged, Strong Construction
Summary: I bought this lens to shoot volleyball first and foremost because the 70-300 f/5.6 lens that came with my camera did not let in enough light. After shooting a tournament this weekend I am thrilled with the results. I was able to shoot 1/200 at f/2.8 with ASA set to 800, giving much better quality that the stock Sony lens could ever do. You'll need a monopod or tripod because it's heavy, which is good! It means it's metal and not plastic like my Sony lens.
Excerpt: I'm very happy with this lens. It's great having a fast lens with this zoom range. I've used friends' Canon 70-200 f/2.8 lenses and this compares well with them. Image quality is just as good. The Tamron is a bit lighter. It is a little harder to autofocus in low light situations with the Tamron, however. That said, I'm not sure that justifies twice the cost. I'm very happy with this purchase.
Summary: I am an advanced amateur and owe a Canon T3i with a battery grip. This lens fits like a glove to it. The overall weigth get a litle bit high, but it is still usable for a reasonable time. The glass quality is amazing (found no lens that overcame it yet) and the construction is robust, but it doesn't have Image Stabilization and the focus is slightly slower then others 70-200 I tried, but the aperture and the cost compensates those small "faults".
Summary: I was looking for a 70-200 range zoom lens for a while. After reading a lot of reviews, I ordered this lens from Amazon and played with it for a couple days. It is a very good lens, produces super sharp images if you give it enough light. Yes, "enough light" is the key to get the full potential out of this lens. Otherwise you will find the downside of this lens: noisy and slow AF, terribly blurry (or noisy) images, etc...
Summary: I wanted a lens that I could use from the stands in high school football night games. It was a toss up between the Nikon and Tamron. I've got a Nikon D5100 camera. I read all the reviews for the Nikon lens, and was going to buy it. I then visited a camera store locally and they said the best second option was the Tamron lens. I'll probably never know how the Nikon differs from the Tamron. But I do know I saved a bundle of money.