Best NAS for Windows 7 & Active Directory

I have a very small AD setup at home with an EON Storage NAS which is a build of OpenSolaris. I didn't do nearly as much testing up front as I wanted to, but it seemed to be a pretty solid OS. The problem I'm having now is the lack of OpenSolaris knowledge I have when trying to optimize performance.

Are there any NAS OSs out there that anyone recommends that:

Perform well with Windows
Have AD integrated permissions
Uses ZFS

I'm running a Cisco (not linksys) gigabit LAN that should be very capable of supporting full speeds. I'm currently getting very slow transfer rates between my current NAS and my windows 7 clients (~10MB/s sustained). That's from a windows 7x64 mirrored SATA disk to a 4 disk RAIDZ ZFS datastore via a gigabit LAN. I am also experiencing dropouts of the solaris box during transfers that I am starting to think are compatibility issues between windows and the OpenSolaris box.

I plan to use this NAS for my VMWare datastore (either via iSCSI or NFS) as well as a media and file server (pictures, SD/HD Video, music). Any recommendations or suggestions would be greatly appreciated.

TravisT

For my VMWare environments, where a cheap NAS is in order, I use a Linux distro called OpenFiler. Has suited my needs very well. I believe that it can do AD integration, but I haven't done anything with it other than iSCSI VMFS systems.

Yea, I've actually used that very briefly a couple of years back. I considered giving it another try, but really like the idea of ZFS, which is currently not offered by openfiler. I think due to the Linux based architecture, it tends to perform better with windows clients, but having the extra features/insurance that ZFS offers would be very nice if I can find a user-friendly distro that performs well. I may build up an openfiler VM just to give it another whirl.