I run hot and cold on poor Kage Baker. I think it depends on my mood and which novel or short story I'm trying. However I have to wholeheartedly recommend that anyone who loves sci-fi (or time travelers, or history, or culture...) at least try her out. She's definitely worth wrestling down your own opinion on.
I'm re-reading the Company novels, and am struck again by how funny and smart they are, by the depth and humanity (?!) of the characters, the sweep of history and cultures she includes. I love Lewis and Joseph. Empress of Mars is also wonderful.