DIY NAS: WS 2008 r2?

Thoughts on MS WS 2008 r2 for a VFX NAS?

Here is the thread on Cow where someone (in Austria I think?) plans to build a DIY NAS with SuperMicro and Adaptec components, 8 spindles and four Samsung Evo SSDs (for caching), to serve five streams to 2K TGAs to about 6-8 Windows clients (AE, Nuke).

Based on their BOM, the budget seems to be around $7-10K. Personally I don't think 8 spindles will be enough, even with good caching, but ultimately I am wondering if using WS 2008 r2 is a good idea for the purpose (of maximizing performance and reliability per $).

Would appreciate your thoughts. Feel free to jump in the thread.

Also, is anyone on this list available to consult the OP (tell them what to get, no post-sale support included yet)? If so, what would you charge? They didn't ask for it yet - I just think they really need it, and I wanted to see if anyone here is available.

Thanks!