For what it's worth, I'm using a Netgear readynas+ here at work with 4 500GB drives in it (RAID5). I get usable throughput, but it's no PC. Reads are about 20-25MB/s on GigE without jumbo frames, writes are at around 12-15MB/s. One thing I really like about the box is the ability to SSH to it and manipulate files locally, I use it for holding security camera storage, and being able to mv 1000's of small files around is nice. Cost is high for what it is though, if I remember correctly, it's about $900 for the device with 2 drives in it. User interface is decent.

Careful, without those red states, you wouldn't eat. That doesn't even take into account the raw manufacturing and export that happens in the heartland. If you factor in the $ + Goods-exported / capita, I'd wager that the agricultural and manufacturing states (red states) come out way ahead.