I do not have any experience on them, yet, and like you, I would like to hear what others have experienced with them.
However, I do find the design interesting, and I am not opposed to a MotorSailor, even as I consider myself a sailor.
As all boats are some kind of compromise (speed vs. displacement
etc.) I tend to focus on function and a big part of that for my projected use of cruising and potential live-aboard is "comfort."
The Islander 40 I have seen online, appears to be roomy, and gives me the sense of "comfort" in the spaces above and below deck
. It also seems a bit "tubby" and so I would not expect it to sail as well as a boat shaped like a racer
. BUT, I have been on some racer/cruisers that would not be as "comfortable" in all the situations I can imagine cruising my boat in (in the future). So, a tradeoff I would accept.