[mxh]

I recently looked at the bandwidth costs of S3 vs. traditional hosting, and found them less than compelling; in particular, they seemed much higher than those of shared hosting providers. EC2 has the same bandwidth pricing structure as S3, so I bet you can do better, especially since 500 isn't that large of a number.

My notes on the subject:

  http://www.mlsite.net/blog/?p=3