Regarding the lens, I dont think there is any need to mention that its awesome...blah blah... I suggest...Dont take anyone's words.
Check it out yourself on DXOMARK. And I suggest, especially see how it outrightly kills NIKON ,CANON & SIGMA counterparts in the Lateral Chromatic-aberration department. Inshort - AWESOMENESS in half of the price of the NIKONs & CANONs.
Its a MADE IN JAPAN lens. I got a 4 year Warranty, which is still awesome. Warranty card stamped by the seller. Got it at much cheaper than the Local-market price, so I am happy.
It was packed well, and delivered in mint-condition.
Overall i am Happy with my purchase. And would recommend the lens and the Seller to eveyone.
I use this on a Nikon D750 and a D7000 and its a razor sharp lens on both bodies. I used it extensively on the D750. Focus speed: 5 stars, its great while working with kids.. now i still prefer a 50 prime but this is a very close second sharpmess: as i said earlier its razor sharp. ive used the 24-70 from nikon and this is maybe better my eyes cannot tell the diffrence build: this is the only area where the nikons win but for 50K less ill live with it low light: Ive seen a lot a reviews where people say low light performance is bad I differ, its not as good as a 1.4 prime but comsidering an overall it focus quite accurately and take better than average photos.