Just wait for the GTX1080 with 2nd Gen GDDR5x.
@Stock the 1080TI is doing 32MH/s on ethash ..with OC I reach 36MH/s
According to NVIDIA the new memory will be deployed along with new GTX1080 too which should make tghen also 32MH/s at stock.
For 1080 11gbps it would be around ~26mh/s - 10% faster then 1080 10gbps version (which is around 24mh/s stock)
1080ti is 36mh/s stock as you are apllying oc to P2 state (which is 500mhz less then P0 game state) = oc'ying for 500mhz results in 5500mhz in afterburner with founders edition