Since it doesn't sound like you're in D1, you're paying the $29 fee per person. For 4 hours I'd say it's worth it. The T4 SC is huge, and since it serves as the club for international flights also has some real hot food on offer. The liquor is not self-pour, but the cheap stuff is free. Any of the premium liquors or drinks (fresh squeezed OH, smoothie) can be paid for with credit card or Skymiles. 1 mile equals 2 cents. So 50 miles per dollar.

Showers are nice, and rarely is there a wait. If there's issues with your flight you can come back and they can assist you. While it's a single visit charge, they won't charge you to come right back in again due to IRROPS.