Hmmm, stay away from 95th percentile billing. That is a blatant ripoff and not a good choice for any webmaster in todays hosting market.
As for your needs... sounds like you are possibly going for overkill with that server setup.
While I am a big fan of a proper raid setup, you most likely only want security and so, all you need is a backup system. Mirroring would prolly be best - and you only need two drives, so you save some bling
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