I am not sure what is causing the slowness when copying from the shares to desktop, 30MBps seems slow to me especially from a stripped 2 x SSD to my desktop SSD.
some options:
copy method
http://forums.servethehome.com/showthread.php?533-SMB-reads-are-slow-on-OpenIndiana-NAPP-IT
nic problem (Windows side)
try other PC
connect directly via a crossover cable
VM problem
try a barebone install
compare to OI live + VMare tools, opt VMXnet3 driver
try more RAM for VM