I've been looking at this zoom lens for portrait photography and travel where I want the reach of a zoom. This lens comes in Nikon and Canon mounts, and since I've already invested in Nikon lenses, I would like to get one of these lenses for my Nikons. I've seen these lenses priced between $1,100 and $1,300, and I've seen reviews on youtube and reviews online saying the lens is nearly on par with Nikon's expensive Nikon AF-S NIKKOR 70-200mm f/2.8E FL ED VR, which is more than double the price. Frankly, I'm just an amateur and not a pro, so I don't want or need to invest in a $2,800 lens. From the reviews I've read, the only advantage the Nikon lens has over the Tamron, is that the Nikon doesn't have the focus breathing issue. So I'm wondering if anyone has this lens and is it really worth the price, or if there is anything comparable or better.