Raid 1 vs. Raid 5?

I’m going to be building a little 750GB raid for photo archives in my existing linux server.

My two options seem to be (2) 750G drives mirrored, or (4) 250G drives in a striped configuration. The price difference is about $60 (more expensive to go with the (4) striped drives). Speed won’t really be an issue, as the network is a bottleneck more than the server read/write speed.

Suggestions on which to do? Other options?