So, I emailed Razer and asked them: "... it is fully functional for Mac? How about the software? Will I be able to customise the lighting effects?"
Their reply: "The Razer Ornata is fully functional with MAC and thanks to the Synapse Software you can fully customize it to your favor."
Going off this and what others have said here, I went and bought it. After fiddling around with the software for a while, I decide to "customize it to [my] favor". Only I can't. Chroma Configurator doesn't work with the Ornata Chroma.