Z170 VS X99 - Which is more future proof?

[magellan]

Both 2011-3 and 1151 will probably have 1 more CPU and will be replaced by next gen. Every socket in last maybe 10 years has 2 CPUs ( SB+IB, HW+BW, SL+? ) but I wouldn't be surprised to see that after Skylake will be new socket as Intel is changing plans to tick-tock.
Anyway X99 is "extreme" platform which generally lives longer so we can expect that Broadwell-E will be better option if you wish to keep pc for some longer. The main reason in this case will be amount of cores as Intel is not planning to release more than 4 cores for 1151 socket while 2011-3 can support Xeons and with Broadwell-E it will be 22 cores max per socket ( if I'm right ).

So Broadwell-E will work in the same motherboard as Haswell-E?

I've read Broadwell isn't very overclocking friendly, but this might not apply to Broadwell-E.

 

[EarthDog]

Yes. Broadwell-e will go in x99 boards.

 

[Woomack]

Broadwell is totally different than Broadwell-E. The same as Haswell and Haswell-E. Only naming is similar but both have different architecture, memory controller, igp ( or not ), cache, pcie lanes, ...
Actually for short period of time there were rumours that Broadwell-E will be called Skylake-E ( there was one slide from Intel without Broadwell-E ). Later Intel changed plans, delayed all series and released 1151 Skylake. I still have no idea why they released desktop Broadwells as they're total fail. Just a product which isn't interesting regardless how you look at it. Laptop Broadwells were released over a half year earlier and were quite good series ( but again different chip/architecture than desktops ).