Now, onto the beast.
Alright, I built this back in November, December, and January (I'll get to why it took so long later) after accumulating the parts over a month or so shopping various sales and looking at the always informative camelcamelcamel
CPU I went with the 6-Core i7-6800K because the bump to a 40-lane has negligible performance increases (a few percent), and the 6800K is already a small increase over the 6700K in gaming applications. After a little tinkering around I have my CPU at 1.275V running 4.0 GHz, I am planning on messing around with it a bit more to try to pump out a little bit more.
CPU Cooler / Fans It works. Replaced the fans on the H115i with the Noctua's, and even on a open case running ultra settings in game and in benchmarks at 3440x1440p, I can barely hear these things.
Motherboard Went with MSI because I had previously built with a MSI board and had no issues with it. It fits the color scheme which is always a plus. Was initially planning on going with an Asus board, but a number of people complained about the boards having issues. I haven't had any issues with this board, but the BIOS was a bit difficult to navigate at first (different setup than the last one I had), but after a few missteps I got the hang of it and it hasn't been an issue since.
Memory "Why do you need 64Gb of memory???" For absolutely no reason. I had 32Gb on my last build because I had maxed out 16Gb using Photoshop, but 64Gb is entirely unnecessary for me. So why do I have it? Because filled slots look nicer than empty slots.
Storage Okay. This is why this build took three months. Initially I was planning on using the Samsung 950 PRO 256Gb M.2 SSD with a 850 EVO 1Tb SSD, but that god-forsaken M.2 drive was a pain to try to get running, and I got tired of trying to get it to work running Windows 10 so I returned the two drives and bought the 850 EVO 2Tb SSD. I had tried about five different "fixes" for the M.2 drive, each of which lasted about a week before sending my PC back to being un-bootable. Have not regretted the decision to replace it.
GPUs Overkill? Yes, a tad. I wanted to run ultra-everything all the time in 3440x1440p and be able to utilize the 100Hz refresh rate of the monitor. SLI hasn't been too bad—knocks on wooden desk. Initially it worked great, and then randomly after a few weeks Battlefield 1 would crash mid-game every time I booted it up, but about a week after it started, new drivers were released and I haven't had any issues since—knocks on desk again. Battlefield 1 was the only game I have encountered issues with SLI—still knocking on wood.
Case This case is beautiful—and makes a lovely space heater. Once I saw Monochrome v1., I knew I had to build my next PC with the Core P3. I didn't get the version with the PCIe extension cable, because I had heard of people frying their systems with 'em, and didn't want to do that. If there's ever a cable which doesn't have many issues and doesn't slow down the GPUs, I'll most certainly get it. All that said, the case is amazing, love how it looks. Be warned, though, the manual sucks. Not informative in the slightest.
PSU It's a box. It works.
Monitors & Other Peripherals I love them all. The monitors, they're beautiful. The Corsair peripherals, they're beautiful. The stand is surprisingly sturdy, but for good measure I used some good 'ol duct tape to secure it to my desk. The guy behind Ensourced does some beautiful work—I highly recommend his cables. I personally went with black, white, and "touch of gray" for my order. Wireless PCI-E card is great and quite fast—the antennas are rather large, though. The Logitech headphones are amazing, but the earpads are rather uncomfortable. Bought some leather replacement ones from ZMF after seeing this Reddit post.
TL;DR: It work. It pretty.