I'm running a 6700K at the moment. I've not run a 4770K before as I went straight to Skylake and just lumped the cost for doing it early-ish. I'd say performance wise you wont see a massive gain but that's not surprising as that's not Skylake's purpose. The M.2 Storage and DDR4 and the fact that Z170 Boards come with all the new kit is the main gain aside from efficiency. Somebody correct me if I'm wrong but certainly with my system Skylake seems to run a little cooler than Older processors if thats a concern for you with overclocking etc. Hope I've at least helped slightly. I'd wait a little longer maybe even until the next processor release if it's the performance gain you're after. Skylake for me was about all the new features the compatible motherboards come with. Good luck !