Dunno why so many so concerned with sharpness. In most cases, if you don't print bigger than 8R or need to crop alot, sharpness is never a problem. There are many other attributes that are important if not more important like
Weight
Size [length & diameter] n filter size
Price
Versatility
VR or no VR
Front end rotates or not
Can use teleconverter or not
etc
Not really true if they have the intention of cropping further?