Sheila, I'm certain you can trust Fred and JoAnn's rec's. Can't add anymore as my experience was with a private guide who doesn't do transfers.
Another time there, we used a company arranged by someone else in my group to tour us after embarkation and get us to airport early next morning at 6 a.m., just can't remember, but could well have been Dream Tours.
Like Fred said, they have been recommended here and on CC for years. Don't think I would want to bother with any public shuttle if your flight leaves at noon.