ESXi + NFS + ZFS = Bad Performance?

I set up a SSD ZFS pool and get amazing performance locally (using dd to write/read). When I mount the storage over NFS via VMWare or directly in an Ubuntu VM, the performance is a small percentage of what I get locally.

Here are the server specs:
FreeNAS 9.2.1.5
Xeon L5640
96GB Memory
24x 480gb Intel 320
Chelcio T520-SO-CR (dual 10G fiber)

I have this set up as Striped 4x raidz2 vdevs.

The benchmarks locally (both compressed and compression off) are pretty good, but when I spin up a VM on...

ESXi + NFS + ZFS = Bad Performance?