Long story short - I like multiboxing and playing Diablo 3 right now. Plus doing some Windows programming time to time (I use Macbook for most of the work-related stuff).
Only reason why I got SLI - I prefer to have 60 FPS for active character while multiboxing and, unfortunately, single 970 can't pump more than 30 FPS on each character (that's 120 fps combined). AMD card was not an option - CrossFire does not work with windowed apps.
32 GB of memory.. why not? Memory is not very expensive, OS can use to cache frequently accessed files, etc. Plus, sometimes I host heavily-modded Minecraft to play with friends, so having lots of memory helps.
Cooler is a beast. I was able to get stable 4.7 GHz with reasonable temperatures, but had to remove front case panel as video cards have open design and blow hot air inside of the case. Installation is not very complex, it is there too many small steps to do and it is time consuming.
Liquid cooling system would be better choice for sure, but I'm not trusting it after friend got his PC fried after a leak. Maybe next time.
SSD is used as a system storage, HDD for Steam and other apps. 850 got new 3D TLC cells and much more durable than 840 series.
Case is decent, but I'd like to have perforated front panel so front fans would be able to pull more air into the case. Also, my previous case was CoolerMaster Cosmos II and, honestly, I liked Cosmos more. Assembly quality, attention to details, etc. And back then I bought it for ~$250, which is certainly more expensive than 750D ($90 difference), but I'd pay extra $100 to get it again without a doubt. Unfortunately, they're being sold for like $450 now and it is totally pointless.
Extra 140mm fan was installed in front of CPU cooler (above it) to push cold air right behind 5" bays and in front of cooler.
I liked motherboard and love that each and every case fan can be controlled separately. While idling or doing some simple stuff like browsing - only CPU fan is spinning.
Reason why I went with ASUS Strix - MSI was out of stock in both Amazon and NewEgg stores. Plus Strix had small discount, so I went for it. Few percent of performance difference didn't justify waiting card for a week, hehe.
I'm going for second 27" monitor and mechanical keyboard (oh, so many choices and I like it to be click-cliky and yet good for gaming, so probably cherry blue or cherry brown). Just in case, full-size Apple keyboard (aluminium one, wired) is awesome, but want to try something else.
And yea, no LEDs - I don't like too much shiny stuff. Utilitarian and efficient.