I've read stuff by Gail and Seanan, and they both rock. I'd be hard pressed to recommend one over the other because what they're writing is so different. Seanan does that wonderful grungy urban fantasy, and Gail does a much more readable combination of Jane Austen and "Wild Wild West," with a dash of Sherlock Holmes thrown in and set in Queen Victoria's Great Britain (more readable than Jane Austen, not more readable than Seanan).