For the Gigabyte motherboard, Killer networking can have some issues. The Killer ethernet utility is useless bloatware but there is an option to only install the driver and not the utility which makes it alright. The VRM heatsinks around the CPU socket are larger than the ones on the Asus motherboard which is a plus for cooling and any potential overclocking you might do. It also has 5 audio ports and SPDIF if audio output matters to you, it makes it easier to hook it up to certain 5.1 speaker sets. The Asus motherboard only has USB 3.0, while the Gigabyte motherboard supports USB 3.1. There's also the metal-reinforced PCI-E slots, but that's more of a gimmick than anything really useful.
Overall, it looks like the Gigabyte model is better. It also costs more, but I think the Gigabyte is worth it for the USB 3.1 support, among other advantages. Not that the Asus model is bad in any way, it just doesn't have as much feature-wise.