I found the comment the reviewer made interesting … Weighs more, costs more, and does the same thing.
http://www.kenrockwell.com/nikon/5018daf.htm I doubt it will be sharper ... perhaps any difference between the two would be at a pixel level ... it's a new optical design and will probably have nicer bokeh, less lens flare and better build quality. Use the one you've got till it stops working or falls to bits, replacing a 1.8 for another 1.8 seems pointless
Totally agree with you, I have the older version, it would, IMO ,be hard to better