I've had my 4770K since July st of last year, overclocked at or over 4.0GHz most of the time, and I've not had a problem yet. Matter of fact I probably have a better overclock now than I did six months ago. Although I haven't had that extreme of an overclock for quite some time, the principles are the same. There's more to overclocking than doing what that guy did, it's not just cranking up the core voltage until it's "stable." That's putting you on the fast track to a new CPU, with ANY chip.
Truth be told you don't even need to crank the 4770K up to 4.6GHz. It'll blow anything out of the water at stock speed, let alone at a more modest OC of 4.2-4.4GHz. As it stands the chip already runs ~10% more efficient than it's predecessor. A 4.4GHz OC on a 4770K chip would about match a 3770K OC at ~4.8GHz.
I think you'll be just fine purchasing a Haswell i7, don't let that dope convince you otherwise. They're just as dependable as any other CPU on the market, and much faster too.