I love these two expansion maps! Britannia is just right for 3-4 players, whereas a lot of other maps seem too big, too small, or too spread out. It's the map I use most for Concordia. It almost always seems to provide balanced, competitive games. Germania is very different from other Concordia maps. The German castles might cause players to play their tribune more often, leading to less predictable games. The map is huge, but you get extra movement points for your boats. It can still be hard to spread out and games have a tendency to end via buying cards before players have built a lot of houses, but I still like it because it offers a very different strategy space despite being less elegant than most Concordia maps.