What an excellent place to stay!
Dean and Matze were super responsive, and even invited me along to watch the sunset at Montague, which was stellar! The space is exactly as advertised, but maybe even better, with really tall ceilings, lots of light, and everything you could need to prepare food except for an oven/stove top.
I used the space to go hiking in South Galiano (I didn't have a car), and it's located close to the Mount Galiano trails and the Bluff trails (which are both excellent), as well as a beach access (though I believe no swimming because of the currents) and you can easily walk to the Montague Marina as well.