I have been working on retiring an old freenas box so I built a nice server with spare parts running freenas 9.xxx x64. I have a hardware raid array (3x3TB raid 5) on a 3ware 12 port contoller. The interface is way different than what I'm used to but I can deal with that. The transfer speeds are horrible though and pause about every 20 seconds. I'm only averaging 5 mbps compared to 55 MB/s on my drobo5n. This is actually a backup for my drobo5n that will get powered on about 1x every 2 mos to update any new files, etc.
I've heard nas4free is a little more solid compared to newer versions of freenas. Never tried it though. Suggestions? Write caching is turned on - still slow as hell lopaka