It has been awhile since I watched this presentationhttps://vimeo.com/141087037
I thought part of the way through, Ruckus dropped some hints that the long term solution for most customers was going to be the virtual smartzone solution. Certainly if you already have a virutalized infrastructure, the virtual smartzone seems a natural fit. Run two of them, one in a data center, and one in a DR site and you have fail-over as well.
I was told that zone director and virtual smartzone run the same code and are now at feature parity