I have rented from David's also. I got exactly what I wanted but did put in my request at 11 months out. I would not hesitate to rent from David's again and plan to do so next year. I also would much prefer to use a company because there is more accountability.
Renting points is usually WAY cheaper than paying Disney's price for a villa or than staying at the resort in a regular hotel room. As mentioned, no housekeeping. Also, the hotel rooms and villas are not the same. Furnishing, configuration, bedding, etc. does vary. A room at the BCV is not the same as a room at the Beach Club, BLT is not the same as the Contemporary, etc. Looking at photos online will give you an idea of what to expect.