Best one is 2699 v3 (non ES)...
if you will overclock it to max turbo (you need to delete microcode from UEFI/BIOS or to downgrade to that one that have no patched microcode from windows you need to delete mcupdate*.dll and it will clocked to max turbo clock)
If you don't want do it than go with E5-2667 V3 ES! it is CPU with extra cache 35MB and 2,9GHz or 2683v3 QS...
One more thing AMD Ryzen it's comming. In one month...
8c@3-4GHz with performance around broadwell-e may be it will be easly overclocked to 4,5GHz. It will cost around i5-i7.
AM4 is much cheaper than LGA2011
My point is if you want to buy one CPU and wait...
... Intel will respone by the time.