thanks again for the advice. a couple first hand comments.
I have to say I was pretty impressed with PTY as a hub. They had a lot of shops to browse (although the prices seem high). The upstairs food court is really a good place to kill an hour. CoolCoil's point about the Copa Club is true. In fact with their flight banks, the place gets so crowded that you cannot get a seat and we only spent about an hour in the club as it was rather calm at first then a zoo of folks stalking your every move for your seat. The bar/tender was the best feature and the food was basically crakers and a latin "chex mix" type of thing.
A few things to point out for anyone else's future reference:
Smokers--not me, but one of the people in our group,and if it's you, then you better bring the nicorette as there is no smoking room in the airport
No money exchange--for some reason thought I saw one on the flight down, but apparently that was my hazy recollection of another airport. Change your money before getting on the return flight home via Panama as you cannot change money inside PTY terminal (or at least past security).
carts are limited. I certainly didn't mind, but at NRT or LHR my wife likes to get a cart so she can nimbly check out the shops...she didn't like lugging her bag through the stores...as I said no worries from me
...but if you do like to shop just keep a light bag with you.
All and all, a 2-4 hour connection in PTY is something I'd do again...especially given the extensive Copa connection options and fact you don't have the hassle of US customs + then transiting to domestic and a fresh round of domestic security screening...much easier to connect in PTY and clear immigration at the end of the line assuming Copa or another carrier flies to where you live
.
One other final thing of note for US bound flights...the Panamanian authorities do a preboarding check of your luggage (everyone boarding) and you are not allowed to bring any liquids...even a bottle of water that you bought in the airport. I assume they wouldn't let you take liquor onto the plane (although as mentioned earlier prices are on the higher side anyway).