Well, I can;'t speak from first hand experience (yet), but I've been researching my quiet computer for ages, and settled on the BQE with 2 Nexus 120mm fans and AcoustiPack, an XP-90 (XP120 won't fit on the MSI K8N Neo2 motherboard) and 92mm Nexus fan. Your proposed parts look fine to me, though you won't need to run the Zalman cooler at 12V - use the included fanmate to drop the fan speed unless you're planning to overclock. I also picked up an antec PSU grommet, some fanmates, a Zalman NB-47J and an EAR Fan/HDD grommet free sample kit.
If you're happy with that PSU, I see no need to suggest alternatives. You may find that once the rest of your system's quiet, you'll notice it more, but you can decide later.
X2 4200+, XP-90 + Nexus 92mm, VTX 5750, SLK3700-BQE + AcoustiPack, 2 Nexus 120mm, Asrock 939Dual-SATA2, Raptor 74GB, Pioneer DVR-109B, S12 430. [url="http://www.silentpcreview.com/forums/viewtopic.php?t=16171"]SPCR thread[/url].
[url="http://www.silentpcreview.com/forums/viewtopic.php?t=48281"]HTPC build[/url] - NSK2480, Biostar TA690G, 4850e, Asus EAH5570 Silent, Minja, 4 GB RAM, WD GP .75TB + 1.5TB, iHES208 BD, Win7MC.