I just thought I'd share with you guys since I didn't find a lot of review on the Sony 18-200mm lens online. A few weeks ago I found the tamron 18-200mm on special at the camera store. (lensandshutter.com) It was selling for $299CAD so I got it on my Sony mount and I was not very happy with the result plus I found a little chip on the lens even tho it was new. Now that happens and I wanted to have it exchanged simply, but they were out of stock so I just paid the 200$ more for the Sony equivalent and I was extremely surprised with the quality and sharpness difference. The sony is much faster and much much more quiet. The 200$ made a huge difference and I will never go back to any tamron lens. Now, I read somewhere that rumours are saying that Tamron may have actually made the lens for sony, but I have no way to verify that. I don't know how it is called in English, but you know when you zoom too much you get purple around your lines. Well, you get a lot lot less on the sony lens. Also the quality and the focus is made much easier on the sony. Also I found my shots are much less darker and much better exposed on my sony lens. In conclusion, I am not a pro and I don't know all the technicalities on the field, but as an amateur photographer I am much more pleased with the sony 18-200mm. Hope it will help at least one person. I really wish I had read about someone that tried or compared both.