A high quality basic running watch. Light weight. JB Hifi and Rebel have both dropped it to $164.
The Forerunner 55 is just out (currently $329 on Amazon), offering daily suggested workouts, PacePro and improved battery life (I can't remember what else). If you have a small wrist, the 45S has not been superseded with a newer 55S - which is why the 45S remained the best option for my 9-year old daughter.