We stayed for 1 week in November, and enjoyed it very much. There had been some recent upgrades (new deck, refrigerator, washer and dryer etc). The A/C worked great and kept us cool at night, the deck was breezy and comfortable during the day. The blender held up for our daily doses of smoothies and Pina Coladas (very important!) Overall the house was great for our family of 4, with the kids sharing the small bedroom and my husband and I in the master bedroom (comfortable king-sized bed). Nice large kitchen for cooking meals will help you spend less on food. The owner was very helpful throughout booking process, and arranged a car for our stay for $60/day (cheaper than the going rate on the island). Manford picked us up at the airport and was very helpful in answering our endless questions of where to go, how to get there, and how to catch land crabs.
One thing that I either overlooked or somehow didn't realize before we came is how close the house is to the Fountain Bay Clubhouse. It isn't shown in the pictures, but it is literally 20 feet from the side of the house. That being said, I think we only saw about 6 people use it the entire week we were there (that could have just been because we were there in the off-time), and we did go over and order a few drinks/appetizers once, so depending on your outlook it could be a good thing.
The bay out front is very shallow at low tide (great for the kids), but deep enough for swimming at high tide. There are a couple of nice snorkelling spots if you head out to the two rocks at the right hand end of the bay (it's a ways out but you can walk waist deep most of the way).
One more thing you may want to consider: It wasn't a problem for us because we love dogs, but the owners of Fountain Bay have about 6 or 7 dogs that run free around the property. They are not all initially very friendly and will bark, but we earned the trust of a few of them and one dog in particular spent most days hanging out on our deck with the kids. If you are not a dog person, you may want to contact the owner and ask if it is possible to have the dogs contained during your stay.
Overall, we loved our first visit to Cat Island, the people are very friendly and it is definitely a great chance to enjoy some quiet time! Bring lots of bug spray (or use Baby Oil), be prepared for high food prices (and check expiry dates on food from stores), visit Da Pink Chicken, but mostly enjoy the experience!