I like Robertson Davies an awful lot, but you have to be a hoi polloi literary person to really get into him. A significant portion of his work is indebted to Canadian history, and more specifically, Canadian academic history, meaning that he, well, wrote for an extremely narrow audience. He was a very witty and funny man, though, and I found it worthwhile to get over the hurdles. Fifth Business is good stuff, as are the other Deptford trilogy books.
Margaret Atwood has her moments, but she kinda grates on me with her tendencies towards preachiness. Nobody likes a preachy woman.