I recently moved from Seattle to San Francisco and let me tell you, it is SO hard to find a great salon. There are a lot of hoo hah type salons that overcharge their customers and treat them like crap, but Derby is not like that at all. I started going to Derby for waxing when it first opened and I was amazed at their prices and the quality of their services.
For those of you who love the quality of Habitude in Fremont and Ballard, but don't love their snobbery, check out Derby. The owner of Derby previously worked as an aestetician at Habitude, but left to open her own salon. Forget driving downtown and paying loads to park, Derby is neighborhood friendly and they know what they're doing. They have great deals, like happy hour eyebrow waxing, and bottom line, they treat their customers very well.
Long story short, sort of, I haven't been able to find a salon as great as Derby since I left Seattle, so go check them out. You won't regret it.