I have one and I have only used it on a 10/100 switched network. I could never get it to work at 100 full duplex, using one of their driver revisions. There is no way we are upgrading to Giga within the next 3-5 years anyway, except maybe servers.
I use a gigabyte its great for general purpose but if you want maximum performance through overclocking than you want an Asus
I've had Gigabyte since the beginning. An amazing motherboard that has always been perfect for my needs - never see BSOD's (which I know aren't necessarily mobo-related but still); and it has been compatible with all of the new products.