SC – All the Airbuses (310/318/319/320/321) were fitted with winglets, much smaller than the A340 winglets, looks like a delta wing on the tips. Some of the new A320 winglets look like the A340 winglets and even old B727 (private jets) get to be fitted with winglets. The B773 got some funny wing / winglet on the tip of the wing, but I don’t know if it’s a wing tip or winglet.
Seems as if the manufacturers do believe it makes a difference in a/c performance.
E