Yeah, I've felt that Sandy seems to overclock pretty well. 4.5Ghz seems to be a sweet spot for my 3820 but this board can't get it to clock much higher than 4.75Ghz without pumping a ton of voltage through it and even then the best I've been able to squeeze out of it is 4.92Ghz. In all seriousness though, regardless of how a 2700k/2600k/3770k/4770k/3820 clocks, they're all going to be about the same with respect to real world performance. They're all good chips that perform very well. I like my soldered heat spreader on my 3820 though.
Indeed, while the performance differences between the models are there, they seem almost academic in real world use. It would tend to make a noticeable difference in particular apps, rather than in a general sense.
It's really retarded that Intel's superior 22nm 3D technology overclocks worse than their old 32nm tech, but it seems that Intel just don't care about this anymore and hence used that inferior TIM on the newer processors.
I just wanna clarify that while my CPU ran just fine at 5.5GHz, it consumed a ton of power and put out a ton of heat, not to mention extra voltage needed to get there. The big Zalman flower cooler I had on it at the time was running flat out too and could barely keep the temperature down. Run any sort of real load on it like Prime95 or whatever and the temperature shot through the roof. I'd have had to use watercooling to stop it overheating with a massive overclock like that, which I'm not prepared to do. Also, I don't wanna kill it quickly with a continual overstress.
Finally, given the crap overclocks on Haswell, if I was building a system now and couldn't get an SB CPU, I'd likely go for the non-K 4770. Depressing for an enthusiast, but it just wouldn't be worth paying extra for a crap overclock.