I bought this lens together with a Tamron SP 70-300mm Di VC USD A005 lens and compared them over the period of one month back and forth. I especially used the Tamron for comparison because it was at that time at around the same price point (around 350 Euro).
The lens\'s auto focus is very quick and absolutely silent; On my then used Nikon D3300 it was very precise and caught the right focus even in relatively dim lighting; The vibration reduction is also quite accurate; The lens\'s sweet spot is at 135mm, where it is very sharp even wide open
Once it gets really dark the lens\'s small aperture was a problem for my D3300 though and focus could not be achieved; Overall, besides being accurate, the vibration reduction was a bit too nervous for me, sometimes jumping here and there and grabbing on the wrong subject.