Further update

booted to a centos live cd, and ran there disc benchmark tool, reports a 400MB/s average 250MB/s

so short of flatting the array and building a linux / win2008 system on it i don't know what else i can test

network seems fine (between 2 W7 machines i can copy quickly" the array seems to match what we would expect from the hardware.

if open-e can suggest something i'm all ears