I've owned this lens for years and it was a bargain when I bought it. With the recent fast portrait glass released form Sigma and the updated Nikon 105E, the used prices of this legend are continuing to fall.
It is just big enough to bludgeon someone with, but not so big that you don't want to bring it with you; Built like a tank, bokeh is somewhere between yummy and delicious; Stopped down, it is a really well behaved, sharp lens for studio portraits
It's biggest sins are lacking weather sealing and flare; but that is even debatable because it handles flare rather gracefully