Bear in mind that properties to the North of Parry Ave fall under Rossmoyn SHS Zone. Most properties to the South of Parry Ave fall under Willetton SHS Zone, some fall under Leeming SHS Zone.
Both Rossmoyn and Willetton SHS's are top public schools in Perth. Leeming SHS is doing very well too.
Like what tnug85 has said, Parry Ave can get busy during certain times of the day (no congestion, just more vehicles running) Bull Creek is a convenient suburb with great facilities and services in the area. You can always choose another street if Parry Ave is too busy for you.
I can't give you a correct answer since I am not living on Parry Ave. Since it's one of the main street in Bull Creek (you can tell from the map), it could be bit busy during rush hour. However, it's convenient since it is close to shoping complex, gas station, gym, parks, cricket/Hokey ground and medical center. The public bus is pass this street.