AdrianPerry

Distinguished
I couldn't view any of the pages you added links for, but the more popular Z68 motherboards are as follows:

ASUS P8Z68-v PRO
ASRock Z68 Extreme4
Gigabyte GA-Z68

These boards are all more or less the same.

One advantage Gigabyte has it that it supports something called "EZ Smart Response" for easy SSD caching, a great feature which basically means you can add an SSD drive at any time without changing the rest of your system or losing/changing any files.

ASUS motherboards (based on benchmark results) overclock higher using the UEFI BIOS than the other boards in this category.

It all comes down to choice really, they are all about the same in almost every way. However the EZ Smart Response for the Gigabyte boards is a great selling point if you ever plan to add an SSD to your build.