Thomas,
Thanks for your offer to run some tests on different OSes and filesystems that you have. Anything you can provide here would be much appreciated. I don't have anything other than our native SmartOS/ZFS based configurations, but I might be able to setup some VMs and get results that way. I should be able to setup a VM running FreeBSD. If you have a chance to collect some data, just let me know the exact benchmarks you ran and I'll run the same things on the FreeBSD VM. Obviously you're under no obligation to do any of this, so if you don't have time, just let me know and I'll see what I can do on my own.
Thanks again,
Jerry