From the prices given by the local distributor it seems K160T-1FBG484 gives the most bang for the buck.
The K325T costs about two times more and it's easier to deal with a smaller package.
There is no schedule yet for the 28nm version.
Half the price, half the logic -> probably half the hash speed -> what's the point?
"two times more" would translate into "a third of the price"...