I can't directly answer your migration question, but, regarding comparison, our team was looking heavily into Cassandra when someone proposed Scylla. We immedi

I can't directly answer your migration question, but, regarding comparison, our team was looking heavily into Cassandra when someone proposed Scylla. We immediately dove into it and was impressed that their claim of being a drop in for Cassandra, as far as our uses go, is totally true. We're using it now as we approach Alpha, and love it. Extra bonus - no Zookeeper!