Corkonian,can i ask what your going to use the dog for i.e,Are you going to use it as a peg dog or a rough shooting dog or a dog for going beatingAs far as taking it out bushing with the terriers and lurchers,that would be a desaster mate if you want a well trained,obedient and bidable dog.
As far as whistles Ferret,the stop whistle is the most important command in a gundog in my opinion and that is one short sharp blast on your whistle