Look at your proposed travel for 2006
Lots of varied and good advice here in this thread. I would have to say the best thing you can do is look at where you will be likely to travel in 2006 and pick the club that will serve you the most often. Quality, features, amenities and size of clubs will vary, but one thing is for certain, if there is no club in the airport you are at that you can access, your choice is moot.
I'd recommend first and foremost finding the club you will have access the most often to in your travels.
Best wishes for pleasant travels in 2006,
CCC