SAN vs NAS for EDA application.

We are planning to establish new hardware setup for EDA (Electronic design automation) Application

Configuration :
Blade server (14 Compute blade : 2 x XEON 5680, 48GB DDR3 memory, OS : RHEL)
FC SAN switch
SAN : Host interface : 8 Gbps FC/1Gbps iSCSI, 600GB 15K 6Gbps dual port SAS drives, 4G cache.

I would like to know
1) Will NAS outperform above mentioned SAN for EDA application/file level access
2) What will be the performance difference if I replace SAS drive to FC
3) Will it be better option to configure above solution as HPC cluster (Note : One Job can be split in maximum 20 threads, due to available EDA tools license)

Thanks