I've been using Maid Experts for about 2 years and very happy with their services. The girl in the office, Susan is extremely friendly and a pure pleasure to work with. Very professional, very consistent. I used to use Molly Maid for few years, but they are more expensive, and their services are not quite as consistent and they would send someone new to my home half the times.
Pros: reasonably priced, professional
Cons: non that i can think of