fact of life: dont judge a knife by its sharpness
okay, to refine that statement: dont judge a knife by its initial sharpness
dont just go by the link posted above, and follow whichever knife seems to slice through carrots better.
how to get a knife sharp? grind a thin, acute edge. thin edge = comes at trade-off of edge retention. want hard steel alloy? then you've got a more brittle knife.
you can buy the sharpest knife out-of-the-box, and within a week of use, without proper care and maintenance (HONING, for example), it will be as dull as the new 15$ one at Target.
so why by expensive knives at all? durability - from full tang. sanitation - from flush, well-fitting rivets. durable handles. etc
so how to pick between knives? choose whichever feels the best in your hand. SHARPNESS is a function of your care
its analogous to shopping for cameras based on a single photo of a calibration card. you can nitpick on tonal separation, purple fringing, barrel distortion, etc... but what it comes down is whether the controls and menus are intuitive for you to actually use the camera to make good photos with...