My last computer was a 2011 Dell XPS 8300 with upgraded RAM (16GB) and video card (AMD Radeon HD 5670). Recently got a Panasonic GH4 and Sony A7S II for my video production and needed something custom built to fit my needs.
The build itself was pretty easy and non eventful. Big thanks to Linus Tech Tips on Youtube! The only thing that was difficult was the front panel USB 3.0 connection to the MOBO - the spot where it connected to the MOBO had a super small clearance and it took a while to get it in there without bending any of the pins. Also had to ponder for a bit where to put the Satechi LED box but I ended up putting it right behind the white cord-cover bar using some velcro tape.
After dialing in the overclock, processor is at 4.4 and about 25% faster on GPU overclock too with no problems with temperatures or crashes.
It runs BF4, Fallout 4, and Shadows over Mordor in 4K in High at 30 FPS. As well as DOTA 2, Skyrim, and Borderlands 2 in Ultra settings in 4K at 60-120 FPS. Capable of showing full 4K previews in Premiere Pro and renders video super fast (if all files placed on SSD of course).