What is Inno3D Warranty/RMA process like?

I'm thinking of buying a used Inno3D GTX 1080 8GB, but I'm wondering what their warranty/RMA process is like. Do you need the original invoice/receipt for warranty or just the serial number? How long does warranty last usually, how long does the RMA process take, is customer service good?

Any other experiences with them?

Living in Australia

Thanks