If these leaks are real, I think Mi4 looks better. There's no point to compromise the thickness because slimmer doesn't always look better. Phones like Mi4, OPO, Samsung Galaxy Alpha, they are slim and have their uniqueness (even though they aren't the slimmest phone), I hope Mi5 is not that slim. Anyhow, I can't determine it by just looking at those pictures. Just my 2 cents. ;)