The standard version is good, but our version of choice is Europe, which is pretty hardcore. Playing either as Russia or Germany is extraordinarily difficult, and there's a good spread of different tactics and ideas to try out.

Pacific is okay, but we generally found it too repetitive, as the game is won or lost in the first two rounds. If Japan destroys the American fleet at Pearl Harbour on the first go and can carry off an invasion of the islands or a further carrier attack on San Diego, Japan generally wins. If it gets a bad result and America can send in a fleet quickly, Japan loses. There's some nice ideas, like the land fighting in China, but overall it's less satisfying than Europe.