winglets

Has anyone tried these winglet-style folding props from T-Motor? Better yet, can anyone even explain how these are supposed to result in longer flights, as advertized, without otherwise being a problem of some sort? https://www.floridadronesupply.c ... ustom-for-inspire-2 Just curious...

Ok I did search this topic but it may be so crazy no self respecting operator would ask, So self respect be darned here goes. Has anyone tried or heard of any rotor quieting devices such as lightweight shrouds, wing tipped rotors (reduce vortice noise), variable pitched blade sets, etc..? Why...