How good is the i5-6600k for gaming vs the i7-6700k

When we talk about gaming then people need to realize something very simple, games require fast core performances. Since the start of pc gaming up until now, games never passed the need for more than 4 cores. So, when you compare these 2 CPUs you can see that they both have 4 cores but the i7 has hyper-threading. Now, the hyper-threading is good for almost anything other than gaming and if you are also editing, rendering and other non-gaming related stuff then sure, the i7 would be a good buy for you. The thing is games are not optimized to use hyper-threading, at least not yet. Games want maximum of 4 cores with fastest speed possible.
In game comparison, the i7 has avg of 5-10 fps max more from the i5 which is better but not for the 100$+ that the i7 has over the i5.
In the terms of future proofing the i7 also doesn’t benefit more than the i5 and the reason is simple, when the i5 becomes low and bad for good gaming experience then so will the i7.
Most popular gaming solution is buying the i5 and overclocking it. Most of the i5-6600k CPUs can reach 4.2-4.4 even without touching the stock voltage so that’s just a steal for the money. So if you are only looking to game on your new pc, even do a light editing or rendering then by all means don’t pass up the opportunity to get the i5-6600k as it is the best price for performance CPU in the world right now.