First and foremost, the "shared" bathroom is a Jack and Jill bathroom that you will be sharing with another Airbnb tenant. This means, you have to unlock the other person's door, when you leave (as do they) so you can each share the bathroom. This is the first time I've seen this arrangement in an Airbnb. I would not have stayed her had this been clear.
Second, it's a bit noisy at night. Closing the window, keeps the noise out, but makes it a bit stuff.
The bed in the "master suite" - which is just a room with shared bathroom is large and very comfy. There was an ample supply of water in the fridge and lots of towels, which was nice.
I stayed only for the night and didn't interact with the hostess.