I love negotiation in games so I am really glad I can get it now for not that much money. I got Cosmic Encounter as my negotiation game but that is still too mechanic in the way that it doesn't seem to work the way this game does since basically anything goes here. Also my group is into economic stuff so it seems to be a better fit in that way as well.
Quo Vadis is a pure negotiation game. Not my thing so I always avoided it like the plague, lol.