I played a game with this yesterday, including AI+. Prince level, to get the feel of things, got randomized into France, so I went very very wonder heavy. As France, I got to see a lot of what the other civs were doing--I noticed they were appropriately building cisterns, for instance. It took quite a bit longer than usual to secure a cultural victory, even with your bonus theming and the belief that buffs relics. I assume that was due to both AI+ and my opponents generating more culture than usual. Very enjoyable game.