I am playing on a giant 43 civ TSL map, King difficulty, regular speed. On turn 121, I see a notice that Maria has built the Great Mosque of Djenne. She has three cities, but no religious buildings. The turn before she finished the wonder, she had accumulated a grand total of four faith points. She had opened the Piety tree, but had gone no further. And all religions were taken as of turn 112. So why would she build a wonder which makes her missionaries (for a religion she didn't found) able to spread three times instead of twice? Okay, the wonder also grants three faith points per turn and a free mosque. Plus, owning a wonder gives her two faith points from the religion she is following. So sum total, she gets: 8 faith, three culture, 1 happiness and 1 Great Engineer point. Is that worth the effort?