Great thread and this case definitely needs a separate threaqd from the HAF one IMHO.
Got my HAF XB a few weeks ago, took my sweet time getting all the parts I wanted to add to it such as:
1) BitBenix Spectre pro 230mm fan
2) 2X BitBenix Spectre pro 140mm fans
3) ThermalTake Water 2.0 Pro closed loop
4) 2 generic Enermax 80mm fans
5) BitFenix Hydra fan controller
First surprise was that the Hydra Fan controller could not be installed correctly since you can only screw one side with the proper tool. This meant that pressing the botton to turn of the fans would push the unitl inside the case. (Not even double sided tape fixed the issue so I had to return it for a NZXT Sentry Mesh)
Second surprise, the top mesh that is supposed to be able to accomodate a 230mm fan doesn't like the BitBenix Spectre pro 230mm fan. Despite the crazy amount holes on the fan itself for mounting, I could never get more than 2 holes to line up at once. I therfore ended up modifying the wholes (after rmoving the rubber part) and installed the fan. Great...well not so great cause of suprise #3.
Third Surprise, The 230mm fan hits the radiator and I can not close the lid... Well that means move the unit to the front and have that sweet warm air flowing over the RAM before getting sucked out the top or the back. This also means that 1 of the front 140mm had to go. So both were removed and replaced with my trusty High CFM Scythe 120mm fans. 230mm had to be replaced with a 200mm non-pro with 1/3 the CFM.
Fourth surprise, despite removing extra cable from my modular PSU and neetly folding and wrapping cables....I could not come close to screwing in the PSU mounting plate that comes with the case to the back of the HAF XB.
Final surprise, save yourself some frustration and dont move thumb screws around. If you take one out, use it in the exact same location as the factory did. You dont want to spend hours trying to screw stuff in cause the screws wont go in straight whn used in different locations (not always but enough to add 30 to 60 minutes to a very quick build)
Conclusion: Its been frustrating but this is the best case I've ever owned. It puts my fully loaded Cosmos S with a modified side pannel ( 2x 120mm 1x 92mm) to shame. Fewer fans, way more silent and my CPU now OCd from 4Ghz to 4.4Ghz and the video cards that didnt want to be OCd now went from 772 to 850 without effort or a single crash and can run at 900 without issues Metro 2033 (to be tested with FC3 this weekend).
Great case, air flow is superbe but dont expect to have space to work. Replacing a HD will be a challange an making any modification to the setup of the lower section means lots of work but fun work). The case has its quirks but is worth every penny even with the funky power botton that I have to press hard enough to move the case (its resting on a mini file cabinet with wheels)
CPU: 17 950 @4.4Ghz
Video Card: 2X Gigabyte GTX 580 3Gb (Windforce cooler)
Motherboard: MSI Eclipse x58
Storage: ADATA SX900 256Gb SSD, Velociraptor 300Gb
Fans: 1x 200mm BitFenix Spectre (non-pro 20mm thick instead of 30mm pro)
2x120mm Scythe SY1225SL12SH 120mm "Slipstream" Case Fan
2x80mm Enermax Slim Case Fan
Fan Controller: NZXT Sentry Mesh
Monitor: HP z30w