I've talked to my vet about this and she said she's done one on a dog and it listed breeds that were unheard of and the dog looked nothing like. Plus, it listed LOTS of breeds for the one dog. I told her she should take a "pure bred" dog and do the test. But it costs too much money to test it out like that. I did not look at your kit for a price. But I would be curious to take my pure bred Aussie and try it out. I'd bet it comes back with more than just Australian Shepherd on it.
Then I saw a show on TV (a reality show) that they did a genetic test on their dog and it said 100% Bull Mastiff. So who knows?