Hi hhhcliff, I have this exact board with an i5 2500k and 8Gb of corsair vengance ram @1600 mhz and a coolermaster 212 hyper evo cpu cooler in a HAF 922 case. I am no overclocking expert and have not had the time to learn as i have only had the system for 3 weeks. All I have done is update the latest bios for the mobo ( which is made extremely easy with the asus 2 software) and pressed the auto overclock button. The 3.3Ghz i5 went to over 4.5ghz stable in about about 2 minutes. From what i have read a manual overclock can yield even better results. At idle the cpu temp is around 26 to 30 degrees celcius and at load it hardly goes over 50 degrees. I think for the price the board is very capable and it also supports two AMD GPUs in crossfire. I am only running the onboard intel graphics as i have been waiting for the mid priced Nvidia cards to be reeased. Even with the intel graphics i have been able to happily play skyrim on high with reasonable framerates ( without aa and all the real fancy stuff ) and also Saints Row the third in direct x 10 and 11 mode with good framerates. The mobo is a solid platform and i dont think you will be dissapointed if you buy it. remember that it is a Micro ATX board and not full sized so you dont get as many pci connectors as on the full sized ones. From my experience so far i would not hesitate to recommend this mobo to anyone. If you have any detailed questions about the board let me know and i can refer to the manual for answers if needed.
sorry I just read the rest of your question. I don't think the x79 boards offer a lot more except the ability to utilise 32Gig of ram and pcie 3.0 ( which at the moment almost no programs or gpus can fully take advantage of) A couple of advantages the z68 platforms have over the h67 boards are intels Srt technology(if you are looking at getting an ssd) and on the asus boards at least is the lucid virtue switching feature that will swap between using the intergrated graphics and the discrete GPU depending on the use scenario ( This is good if you are concious of power consumption). i personaly couldn't justify the extra money on the newer boards for my use case. My personal opinion is that any tech you buy today will be really outdated in 2 to 3 years time so buying the most expensive components available is not the best value for money when chances are you will likely replace most of it in 3 years anyway..
