I have a bird hitch, it works ok on ducks and small geese. Big Canadas not so much.
The wild wing slinger looks like a far better way. If you know someone who can weld you could make on easily for cheap.
I think, one point to note on the wild wing, is the birds were gutted already.
The H2 version of the bird hitch looks like it solves the Canada problem.
May help with broken winged Snows and Specks also.