Hi ive heard about these "dog training collars" which are used to controll dog barking, they have a unit which goes round the neck and a spray nozzle which sprays a mist of air onto dogs neck or nose, they are set off either by when the dog barks or by a remote control, does anyone else agree with using theses?

Citronella training collars can work very well, when used by en experienced trainer and after trying other methods of bark control. Are you working with a trainer? Bark collars (Citronella or stimulation) are a good last resort when other forms of training are not effective.

For me dog training collar is good...
It is effective...
just used it properly and you will have a good result...