There both good motherboards so it's down to personal preference.Personally i would go with the Asus motherboard myself.
It all depends what you're using it for. I own the P5N-E SLI and wish I didn't, but I also know somebody who's been through hell with the Abit. If you can track down a GA-965P-DS3, go for one of those, they're better than either, but hard to find these days. If not, go with something like an Asus P5K-V.