IOPS in SANHQ doesn't match Windows

I'm doing some testing with in-guest iSCSI using the Microsoft initiator. I'm noticing that the disk writes/sec doesn't come anywhere close the the iops reported by SANHQ when looknig at the live view for that specific lun.

Watching the live view of SANHQ I see peaks of 200 or so iops.

In windows I'm looking at perfmon and viewing disk writes/sec and i'm lucky to hit 40.

Does anyone know why Windows and SANHQ report such different numbers? Why is SANHQ seeing twice as many iops as windows?

Thanks