The site sourced comparable parts from a 'large, nationwide internet retailer well respected by do-it-yourself PC builders' to build a system similar to the $9,599 Mac Pro configuration which offers a 2.7GHz 12-core Intel Xeon E5 with 30MB of L3 cache processor, 64GB (4x16GB) of 1866MHz DDR3 ECC RAM, 1TB of PCIe-based flash storage, and Dual AMD FirePro D700 GPUs with 6GB of GDDR5 VRAM each.
Lian Li's stalwart PC-7B ATX-compatible case was chosen to house the system. A Corsair's CMPSU-650TX 650-watt CrossFire-ready power supply, an Asus Z9PE-D8 motherboard, two AMD FirePro W9000 GPUs, Intel's Xeon E5-2697 Ivy Bridge chip, an OCZ RevoDrive 3 X2 series 960 gigabyte PCIe drive, and Kingston Technology 16-gigabyte, ECC-registered DDR3 1866 RAM modules were put inside.
All components considered, the Windows equivalent cost $14309.89. That's without offering Thunderbolt or an equivalent to AppleCare. Thus it would seem that despite its high cost the Mac Pro is a good value.