An oldie but a goody...
Yes, the B707.
Flaps 40 or 50 were fully approved as a landing flap settings, flaps 40 increased the landing distance by an (average) 600 feet.
In addition, flaps 25 were used on occasion, for stage three modified aircraft, to achieve specific noise requirements and, in this case, the regulated landing distance was increased by 1200 feet.
Not a problem where the landing distance was not limiting.
One operator (PanAmerican) normally used flaps 40 for landing, to enhance control during gusty crosswinds...HKG, with southerly gusty winds, for example.
Been there, done that, and it works just fine.
As usual, follow the specific airlines' recommended procedures which, if you follow 'em, you cannot be faulted.