ok i would go with some of these components id did not look in depth on those sites so i do not know if they are available so i will list a few different parts. and i would look for some of these parts used for example a cpu is pretty hard to kill and the chance you get a bad used one is pretty rare.
cpu---- 2X X5677, X5690, X5680 these are a bit older cpu's but they will preform close to the e3's and you could get 2 for the same price.
motherboard---- hp Z800
Ram---- Registered ECC memory sets of 3 sticks per cpu (1333 mhz)
GPU---- GTX 690, Titan X, 980 Ti, HD 7990, GTX 780 Ti, 980, Titan Black
Hard Drive(s)---- samsung evo SSD, OCZ trion 100 SSD, Raid 0 with WD Velociraptors (i got the same performance out of 4 of these as one OCZ SSD)
with 2 of these cpu's you would get significantly better multi core performance and about the same single performance. you also have 12 slots for ram instead of 4 giving you MUCH more max ram capacity. ECC registered is also pretty cheap to get