Of the chain stores who tends to get the most diverse range?

I ask because my husband has been looking (in Sydney) and eventually found a whole pile of stuff my son was after in K-Mart of all places... I expected Toys'R'Us to be better but hubby said their range was pretty limited in comparison...

On the plus side he has picked up a a few goodies that sold out/weren't released here that my 7 year old has been after for over a year.