Vote for ASUS P6X58D-E, but Rampage III is also good. Similar, I think. The price diff is only small. You can't go wrong with both. Gigabyte is good too, and has lots of mobo protection unique features. But some people has 'Usability issue' with memory. But it's overall also a durable motherboard, and can get overclocked high.
Actually, you can choose any of them. All provide good warranty too.