Uh, don't know what the heck you're talking about because the Z's screen is worse than the MBP, I'll explain..
While the Z has an amazing screen, very bright, very crisp and colors are rich, the problem is the horizontal viewing angles are very poor. The Z needs to be viewed spot on in order for it to look good. If two people look at it together it will appear yellowish because of the color shift.
True, both the MBP and the Sony have color shift due to being TN panels but the MBP has a much wider horizontal viewing angle before the color begins to shift and when it does shift it's very slight vs. how yellow the Z becomes.
Also you need to compare the matte version of the MBP because the Z (at least the ones I've tested) come with an antiglare screen. The glossy MBP's look different than the matte. The matte has a more natural look in terms of color uniformity. Take your Z to an Apple store and compare it to one of the antiglare MBP's.
The Z's 1600 & 1080p screens are better. The colors are insane on the 1080p. Although, smaller offering higher PPI. To comfortably use the 1080p screen, you have to scale the DPI on most apps. Some can hand with the tiny print, buy most cant. However, movies and photos look stunning.