I've had memberships to some pretty amazing, full-service gyms back when we lived in the city & the Airport Health Club goes above & beyond. In terms of classes, fitness apparatus, & facilities, they have just about everything -- aquatics, tennis, racquetball, basketball, volleyball, yoga, pilates, spin, weight machines, cardiovascular machines, a Curves-like 20-minute circuit, & more. They also have an indoor & outdoor hot tub, sauna, steam room, various pools (all heated, except for the lap pool), & free childcare with membership.
It's gets busy but never feels over-crowded -- even at peak times of the day. They offer all sorts of classes throughout the day & evening (most of which are free with your membership), & you can almost always get into the classes or onto the machines you want with minimal or no wait. Their level of service is incomparable. They provide cool water & ice cubes with lemons & large, fuzzy towels which are often pleasantly warm from the drier. The locker rooms have dispensers with nice soap, shampoo, conditioner, shaving lotion, deodorant, & hair spray so you hardly have to bring anything. The lockers all have their own keys, so you don't need to lug heavy padlocks around either.
If you have children, the Airport Club is a particularly good value because: (a) the kids enjoy hanging out in the childcare rooms (sorted by age) & do fun activities & receive excellent care while mom & dad get to work out, enjoy the hot tub & sauna & steam room, or get a haircut or manicure/pedicure at the in-house salon; (b) they offer yoga, fitness, tennis, swimming, & rock-climbing classes for elementary school-age kids (some free, others for a reasonable fee); & (c) the kids adore the pools & outdoor hot tub. For athletic kids, they Gym also offers fun summer sports programs.
The monthly fees are reasonable once discounts are applied (through most health insurance companies as well as Triple A). We have a crappy small-group health plan with Blue Shield & still got a $30-per-month discount, which brought our monthly membership costs down to a rather reasonable $130 per month for our family of three.
The main obstacle for most folks (including us) is the up-front membership fee (a whopping $750 for a family of three or four). You have to plan ahead & save up or dedicate your tax refund for this purpose. Their occasionally-offered new-member specials (we got $200 off the membership fee, plus one month free) also help a lot.
Coming up with this money was hard, but I also feel it's a necessary part of their business model, so they have the capital to expand capacity as their membership grows & maintain their current level of excellent service.