I was an early convert to Pro Sports Club's Seattle location. Peaceful, spacious, rarely crowded. Good locker rooms with key-less lockers (you set the lock code). I loved the massage therapists there, esp. Jen---who is INCREDIBLE. You want a knot in your back gone? Go to her. Tip her well. She's worth what you're paying for.
Despite these experiences, I grew tired of the unresponsiveness of Pro's management to member suggestions, or even requests to pause membership while working out of town for several months (this is something that many other high-end clubs in Seattle do for members--common in a town where there's a lot of fisherman away at sea).
The treatment and stories I heard from staff also made me concerned about how I was spending my money at Pro. Every few months, the young front desk staff would change---so I wouldn't be recognized by anyone by name for another 2 months, or would get asked "did you check in yet?" when I'd been there for an hour. Pro's money is in personal training, and they do have some good personal trainers, but the good ones are dreaming of a day when they can be out of Pro, away from the pressure of converting to a conservative evangelical church, and finally getting health insurance (trainers tend to vent when you're on the treadmill). The nutritionist I saw there, when given my diet journal and all the information she requested days in advance, didn't reflect on any of it in my appointment. $75 to be handed copies of recipes and told to keep my diet under 1,700 calories a day-- a waste of money.
Unlike other high-end clubs in Seattle, Pro Seattle didn't have social gatherings for their members, so if you're looking to meet new people or do networking (I'm not talking about meat markets, rather, building friendships) you won't have opportunities.
There are other great gyms to consider in Seattle--- Rain, Olympic, WAC, Seattle Athletic Club. Find the one that fits you best and reflects your values.