My experience is that they go down every 2-3 years, usually the problem is with the hard rive, occasionally with some other component. Under normal circumstance

My experience is that they go down every 2-3 years, usually the problem is with the hard rive, occasionally with some other component. Under normal circumstances it takes them up to one hour to replace the hard drive, and then the array gets rebuilt for a few hours with the system being online. That means something like 2 hours downtime every 2-3 years, that's quite acceptable for my usage scenarios. In terms of money spent during that time, the difference is enormous.