Thanks for the samples.
Many lenses are actually sharp in the centre but soft at the edge especially wide opened though.
The fact that lenses like Nikon 17-55mm f2.8Dx is so expensive is actually quite funny to me as people don't blink an eye when they go all out to buy such lenses and then others would scream bloody murder when they hear that Olympus ZD lenses can cost $1.6k to $2.6k for super high (pro) grade and high grade lenses which are critically acclaimed and pin-sharp. :dunno:
Yes, that's true. But now you do see many lenses with straight line MTF thanks to aspherical optics which corrects the spherical aberration which is the main cause of corner blurs.
I'll have to agree with you that Nikkors are bloody expensive..
Certain Olympus lenses has a wierd complex distortion which can be hard to correct. I will also have to admit that in each camp there are good and bad optics. Even Carl Zeiss and Leica are no exception.