Haswell can offer up to a 10% performance gain clock for clock over Ivy Bridge. If you plan on overclocking then Ivy Bridge would be a good choice if you can get a K series CPU at a decent price. So in a way if you took the 4770k which on average people are getting 4.2. to 4.4ghz and then pitted it against an overlocked 3770k which I guess most people are getting 4.5 at the least there even closer in performance. That and though Ivy Bridge does get hotter than sandy bridge it is still not as hot as Haswell if you care about temps and what kind of cooling you would need to invest in to keep that Haswell K series running cool. That is my two cents.