I have visited Cape Breton twice - once last year ('07) and again this summer, and stayed at Cabot Shores both times. My stays were both short, not month or summer-long rentals, but I can say that they were both wonderful. The chalets are spacious and extremely comfortable and the setting is, in a word, beautiful- within walking distance of the water. Besides the place itself, Paul and Barbara, the rental's owners, are warm, hands-on hosts.
On both trips, I ended up spending a lot of time in the lodge, a sort of community gathering/eating place and met perhaps the most diverse group of people I'd ever encountered in my life - a worldwide traveller from Ireland who was next off to Argentina, a completely kosher New York City couple who'd just married mid-life and were on their honeymooon, a group from Denmark who had come for a week of fly fishing, as well as an Indian guide named John, who is employed there, instructed me in how to make a tee-pee, and whom I now consider a friend.
This is easily one of my favorite vacations and I will be going back again.