I worked well. There was a bit of a learning curve, but I have that may have been my own shortcomings, instead of a weakness of the interface.
Roll20 easily utilized my webcam and mic, I unfortunately, didn't have my headphones or speaker with me. I was having trouble seeing the map as a player, but when I logged out and logged back in as a GM, everything went fine.
Assembling an encounter or importing maps from the web is a snap. And I was very impressed with it's easy to understand interface and self-explanatory toolset.
There seems to be a wide assortment of tokens to use for the player and GM and I see it being a major toolset in my future.
The die roller is great and it keeps track of your last 10 rolls, which was a huge help last night.
I used my MacBook Pro and had no trouble getting everything working.
I really can't praise it enough. I haven't used other Virtual Table Tops, but at this point, I see no reason to seek any more out.