Illumynization :
Starting with the RAM. They are both excellent modules. The performance difference you be 0%-.01% so just pick the one that's most appealing to you (They were the same Speed and CAS, right?).
As for SSD/HDD. You can RAID 5 if you'd like. You can Also JBOD too. I have 3 SSD's and 1 HDD. I use one SSD for Windows and Misc programs. I use the second for more space, installing games and other programs onto it. I use the thrid SSD as a Cache for the HDD. Lastly, the HDD stores all of my videos, pics, music, and other programs.
I use a HDD because it offers more space at a cheaper price but has a slower speed. Since I don't need the speed for such files it's ok. If you can go for something like 1.5TB - 2TB of SSD storage and think that will be enough, go for it. Otherwise, get SSD's as you see fit for however much storage you need, and get a large HDD for the rest.
Ok, I think its time for a big roundup of the various components everyone has listed. I am not familiar with using PCPartPicker so I just manually put in some hyperlinks to the relevant websites. As always this proposed setup can be challenged by someone that thinks they have a more powerful solution.
CPU : Intel Core i7 4930K
http://www.amazon.co.uk/Intel-Hyper-Threading-Technology-Virtualisation-Directed/dp/B00EMHM622
GPU : (3-way SLI) EVGA GeForce GTX 780 Ti Classified K | NGP | N Edition
http://www.evga.com/Products/Product.aspx?pn=03G-P4-3888-KR(is the performance boost with this worth it, as in a comparison it did fare better in some aspects)
Motherboard : Rampage IV Black Edition http://www.asus.com/Motherboards/RAMPAGE_IV_BLACK_EDITION/
Or
ASUS Z9PE-D8 WS Dual LGA 2011 Intel C602 SATA 6Gb/s USB 3.0 SSI EEB Intel Motherboard
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131817(is this even a contender? It was recommended to me by someone)
Memory : G.SKILL Ripjaws Z Series 32GB (4 x 8GB) 240-Pin DDR3 DRAM
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231507
Storage : Samsung 840 EVO
http://www.pcworldbusiness.co.uk/catalogue/item/P174266P?awc=2371_1394381106_b581daaf38c2208eeba9880dd3c7a8d9
(I am starting to think I would be better of with just one. Is this purely a question of how space I actually need?)
Case : Corsair Obsidian Series® 900D Super Tower Case
http://www.corsair.com/en-us/obsidian-series-900d-super-tower-case
PSU : (as of yet unreleased) Corsair AX1500i Power Supply
Optical drive : LG GGW-H20L Blu-ray Drive/HD DVD Reader http://www.pcadvisor.co.uk/reviews/pc-peripheral/1499/lg-ggw-h20l-blu-ray-drive-hd-dvd-reader/
Sound card : ASUS Xonar Essence STX
http://www.asus.com/Sound_Cards_and_DigitaltoAnalog_Converters/Xonar_Essence_STX/
Cooling : This a whole other beast and for a build such as this I will be opening a different thread specifically to help me build a custom water loop after I have finalised the parts on this thread.