Gigabyte are the ones I see fail the least when working in repairs. They're definitely made more reliable, and all the boards I've had were rock solid, bar the Realtek AC97 audio in two 2004 boards deciding not to function after about 4-5 years. Not sure why, but happened to both.
I would definitely recommend gigabyte, but their support service has been woeful in helping me with my MA78GM-S2H. After a little complain I'm getting somewhere now though, refreshingly.
Asus I have found to be slightly flaky, same with MSI. Abit were always pretty reliable, Asrock tend to be cheaper but not bad, never owned an intel board (of any merit at least), and certainly not an EVGA!
So GB it is, and my next board will be one of theirs.