Regarding the cases, I would go for the HAF X, I heard the storm trooper has issues like when you touch the side of the case, it turns off the computer ect.. I would go for the HAF if your choosing between the two.
Just to be safe, I would go with a 850W PSU, always better safe than sorry! Especially like Zka mentioned, if you plan to OC and get more GPU's for xfire or 3 way sli, you will need the exra power! ( I use Seasonic 860w platinum)
The corsair watercooling units require no mantinence at all, except dusting radioator like Zka mentioned, I have the H70 Core, which is the H80 without fans, Seems to do the job, just make sure you get an aftermarket thermal paste, like arctic silver or whatever is your preference!
I'm with Zka on the memory, Vengeances do cause trouble..
Fans.. Whatever you like! I use the cooler master LED fans, but may get a cold cathode tube later on and get better fans.
Good Luck with your build!
😄
Case - Cooler Master Storm Enforcer
Motherboard - Crosshair V Formula
CPU - FX-8150 3.6GHz ( OC'd to 5.4)
CPU Cooler - Corsair H70 (2 gentle typhoon fans)
GPU - ASUS Radeon 6850 HD 1GB
RAM - G.Skill Ripjaw X series (2x4gb) 1600 (OC'd to 1725)
PSU - Seasonic 860w platinum
HDD - Seagate Barracuda 500gb
SSD - Corsair Force Series GT 120 GB
OS - Win. 8 Pro 64 bit