If you ever practice 2-sided PLL recognition, the R2u... G-perm, its mirror and AUFs will really annoy you. Everything els eis really nice, but those 8 are the ugliest and most confusing compared to the others -they have few distinguishing color features, and subtle stickers matter much to distinguish them (compared to, say, an H-perm, which is really easy from all angles).
And if you don't practice 2-sided recog, the same difficulty is still there.