Well, orange defo works against cats, been a cat owner for many years.
Another one to try might be worth a try (a friend of mine has used this successfully to control a next door dog barking all night)... obtain some UHF Mp3's (the ones only cats and dogs can hear), when you spot the offending moggy, put it on, crank up the volume on the pc and stick a speaker out of the window. If its at night you can leave it looping.
Not as obvious as sendin the cat home with pellets in its a*** and definitely effective.