I've been using at the Seattle Athletic Club (Northgate) for about a year and LOVE it! I have a 1 1/2 year old, and the SAC is my haven. The 'Kids Court' child care workers are great, really take the time to know the kids, interact with them, and make sure they're comfortable there. They even have regular Parents' Afternoon/Morning Out events - great for going to appointments, doing errands, or just catching your breath :).
The club amenities are quite nice - towel service, sauna and whirlpool in the locker room, newly renovated pool, nice Cafe upstairs, and a conference room you can use for meetings or to get a little work done. They have a Wifi network, too.
The equipment is all up-to-date, including some new personal TVs at the treadmills and elliptical machines. They give you a free fitness assessment and workout plan when you are new to the club - a great bonus whether you're just getting started, or need some variety in your routine.
Our dues are subsidized by my husband's company, so I'm not sure of the rates. If you call or stop in, they'll give you and information packet and some day passes so you can check it out for yourself.