After ruling out AMD it was between this and the 5920k; I wanted the extra lanes even though I will probably never use them. Also I'm not very familiar with OC so the clock was nice. Currently running at 3.75
For me, the i7-5930k sits right at the sweet spot of Haswell-E processors - it's got the 40 PCI-E lanes for the SLI plus the higher base clock speed, with only the loss of the 2 cores from the much pricier 5960k. A great processor all around.
I knew I wanted a 6-Core i7, so it was between this and the 5820K. I had a little extra money to burn for once in my life, so I figured I'd get the added expand-ability of the extra lanes, and a little more speed. So far it's a total boss. Aftereffects compositions that used to take 45 minutes to render on my old Lynnfield i5 now finish in 3 minutes.
This CPU has been amazing. It has laughed at everything I have thrown at it so far. While it is not overclocked yet, I do plan on doing so in the near future. Originally, was going to go with the 5820k, but at the price I got this for, I just could not pass it up.