Seems to be working well after a few weeks
Got the most unbelievably fluffy thick-coated rescue moggie and had great problems with furballs all through winter, so I was really concerned what would happen when the weather gets warmer and she sheds even more. I've fed her the Royal Canin along with wet food and a few Whiskas Antihairball treats for the last month and so far, so good - none of those dreadful coughing/wretching sessions since! - so fingers crossed, this will continue to be a good solution for her.