Yeah it's by no means perfect. Another problem that comes up is that when one drive fails the load on the others increases, which can lead to more failures. It'

Yeah it's by no means perfect. Another problem that comes up is that when one drive fails the load on the others increases, which can lead to more failures. It'd be really interesting if someone's looked into the stats here but I haven't seen it. As for paying for the power+drive bays, that's true of the consumer NAS devices but if you buy used servers instead it isn't such a problem. For the price of a 12 bay Synology disk station you can buy a 24 bay, 4U, used Supermciro 846E16-R1200B with a couple of CPUs and 144GB of RAM. Not a great choice if you're short on space but can be decent otherwise.