Depends, if you are after higher framerates and have a high end graphics card and high refresh monitor, then yes it's probably worth it.
I had a 6700K for 3 years, for the first 2 I had it overclocked at 4.5, for the last year after a bIOS update I didn't bother overclocking except to enable MCE which is technically a mild overclock. Honestly I couldn't tell the difference because I never really pushed the CPU that hard in the first place.
The other way to look at it is, if everything is running fine as is then why overclock? what will it achieve exactly?