I've found all US RCC clubs fine on TMobile.

Within USA terminals of course is a total crap shoot depending even on where you are within them.

I missed a flight last week in LAX as I came out of RCC, saw a 767 to IAD delayed, and not even started boarding, so went back into RCC for only 5 minutes to send another email, and came out and doors were locked. The fastest loading 767 in UA history. If one knew laptop WOULD work at gate, less tempting to do that.

Even the alleged RCC in SYD (Koru Club) did not work for me last week on wireless.

In 2009 why all major airports worldwide are not free signals for everyone sure beats me.

Cost is VERY small to offer it.