My understanding is a team ported the ESS "Shark" code from AIX to the little Linux 2.x embedded controllers. It looked like Adaptec OEM hardware when I tore mine apart. I can see how that would go poorly versus the proper cabinet sized arrays. They are definitely good enough for home use but I agree not what you want any production workload on. I heard from a 3rd party support company there is some part that is prone to failure but I cannot recall what it was.