Whether or not the maintenance is any good, as a passenger the best airline I've flown with in terms of apparent maintenance (i.e. everything looks like it work

Whether or not the maintenance is any good, as a passenger the best airline I've flown with in terms of apparent maintenance (i.e. everything looks like it works) and cleanliness is Emirates. I flew with BA a couple of months ago (in business) and the aircraft were filthy and very old.