I have a 7700K de-lidded and can run it easily at 4.7Ghz at 1.15v but I don't bother, I just leave it at 4.5Ghz at Auto volts in the bios since, the performance drop's on the CPU by dropping the voltage.
I only game on my main machine now, and don't really need to overclock it even when rendering a video on it, if my other machine is busy.
My next chip will probably be capable of overclocking but I probably won't overclock it, since I just don't need to but for the sake of usually around £20 I don't see the point in not buying the version that cannot be overclocked, that is unless I go AMD for my next one.