I like it so far, just fear a little the replay value after I finish all the cases, though I'm only at case 6 so far.
When I played 2 cases together with a friend yesterday, we noticed that often we were so much in this truth, doubt, lie - game that we looked too much at the facial expressions (and not to forget the gestures), rather than just asking: what motive has this person to lie or withold information, or if they have a motive at all