All four of the IAH clubs are similar in most respects. The selection of snacks and drinks is the same at all of them. One of the C clubs has showers available, but that is the only thing that really makes it different from the other club in C. The B and D clubs are smaller and generally less crowded than the two C clubs. My rule is just use the one closest to your gate. I do have a personal preference toward the B and D clubs though, because they are usually quieter and have fewer people in them.
[This message has been edited by ssullivan (edited 09-13-2003).]