Many people have Gigabytes and swear by them, they're a reliable brand and I'm sure either board will work great for you. I like MSI's K7N2 Delta nforce2 boards myself
totally kickass board! using it right now. NOT for overclocking, but if your looking for a solid board with tons of features, this baby got it. I have had 2 gigabyte mobo's and i swear by em. You wont be disappointed.
I think I might actually get a Gigabyte. I'm thinking about the Asus A7N8X but I'm kinda worried about memory compatability. I've already RMAed 2 boards and I don't want to go though another one.
I recently pondered the same question, I elected for the Asus A7N8X because of its excellent overclocking potential. I put two stick of generic DDR400 ram in and run it dual channel, I have a 2.5 running at 2.2 which gives me a 3.2XP - It runs Rock solid!
I have had problems in the past with gigabyte mobo's, but I have used them recently on new builds and I am quite impressed with their options and quality etc. They are not the best for overclocking though.