9 out of 10 points and recommendedAccurate and fast autofocus, good build quality and sharpnessMF ring not so good
I've bought this one after one trial week with 85 AF-S and AF-D.reviewed May 16th, 2011 (purchased for $1,000)
While 85 AF-S is a bit sharper and has better corners , (but not by much) is it also 700 euro more expensive than the Sigma.
AF-D version is weaker in almost all respects, except maybe on bokeh ( probably those soft corners are helping here)
Fast and accurate AF, on a D300 using any mode ( including mounted flash + AF-assist illuminator ).
I think it is the fastest 85 f/1.4 lens. (AF speed wise)
It is an excellent lens and good value ( considering that AF-S is 700 Euro more , respective 400 Euro for the AF-D version.
..but as with any lens it is good to test it first!