First water cooling build

Hey guys, I'm new to watercooling but I've built plenty of air cooled systems, I've been researching for a couple of days but could do with some guidance and advice  .

My current hardware:

Fractal Design Arc Midi
Gigabyte P67A-UD4
i7 2600k
850w PSU
MSI GTX 580 Twin FrozR II/OC
Gigabyte GTS 450
Xonar Essence STX + H6 Expansion
2-3x SSDs
1x 3.5 HDD
1x RX240

And here's my plan:



I'm going to put my SSDs in bay 1 with a slimline optical drive, and my 3.5 drive either in bay 2, or fix it underneath the bays, above the front radiator.

Shopping List:

Liquid:
Mayhems Ultra Pure H20 Water

CPU Block:
EK Supremacy Nickel+Acetal

GPU1 - GTX 580 Block:
EK FC580 GTX DirectGPU Nickel+Acetal

GPU2 - GTS 450 Block:
EK VGA Supremacy Nickel+Acetal

Radiators:
1x RX240 bringing total to 2

Pump / Reservoir:
Laing DDC1+ Ultra Pump 600 L/hr with XSPC Reservoir Top
2x Mayhems Fine Silver Kill Coil

Tubing:
I've been reading and it looks like 3/8 tubing would probably be best for flow vs space, and also that tygon is regarded as one of the better makes. So I'm looking at: Tygon R3603 3/8 ID - 1/2 OD (10-13mm) Tubing : Clear

Fixings:
After much consideration I've decided to go with compression fittings, as they're easier to use and safer.
Alphacool 1/4 Thread Compression Fitting for 3/8 ID - 1/2 OD Tubing : Deep Black
Alphacool HF 1/4 Thread 45 Degree Rotary Compression Fitting for 3/8 ID - 1/2 OD (10-13mm) Tubing : Deep Black
Alphacool HF 1/4 Thread 90 Degree Rotary Compression Fitting for 3/8 ID - 1/2 OD (10-13mm) Tubing : Deep Black

Fans:
I'd like them to be as quiet as possible, whilst still doing the job. Also I'm unsure if I need to have 2x 120s for the front radiator, as there will be 2x 140 in the front bezel?
3x 140mm (2 front, 1 rear) Xigmatek XLF 140x140x25mm White LED Case Fan : XLF-F1455
2-4x 120mm Xigmatek XLF 120x120x25mm White LED Case Fan : XLF-F1254

Controller:
I'm quite lost here, It is possible to free up one of my bays, but someone who did a similar build to mine used this- mCubed HFX 113 T-Balancer BigNG Cooling Controller and I quite like the look of it, especially the software.


Can anyone see any improvements that can be made for my shopping list, or anything I'm missing or doing wrong? Also the on the VGA Supremacy product page of the EK website, it says 'Covers only GPU. You have to arrange passive cooling of RAMs and Mosfet chips.', should I be looking to get some passive heatsinks like these for it? Or would the case/radiator fans be sufficient? Also I've read that people have had problems with EK nickel in the past, but these issues are resolved now, would it be best to stick to plain copper?

Thanks very much