Seeing how memory isn't all that expensive anymore, it's definitely not that bad... 1tb usually runs around 60-70 bucks now, so for a couple hundo, you can basically build a raid stack...
the real issue is how expensive cards are, and how fast you'll fill a card by running raw...
but... for the quality you already get from .mov files and such, really, there's no reason to even think about doing this for the grand majority of folks. The flexibilities being opened up, however are really cool, if anything.