As we're designing our systems for a move from mysql to Cassandra we're considering moving our file storage to Cassandra as well. Is this wise?

We're currently using mogilefs to store media items (images) of average size of 30Mb (400k images, and growing). Cassandra looks like a performance improvement over mogilefs (saves roundtrip, no sql in the middle) but I was wondering whether the fact that cassandra stores byte arrays should encourage us to store images in it. Is Cassandra a good fit?
Has anyone had any similar experience or can send guidelines?
To phrase the question in more general terms: What's cassandra's sweet spot in terms of Value size per column or total row size?
Thanks