No, in some cases it's not ok. Imagine you poll your Joystick every 500 ms.
At t1 = 120ms, you press the X axis, direction : left.
At t2 = 230ms, you release the X axis.
When you'll poll the joystick, at t=500ms, you'll get 2 axis events, but when you will want to get the value using getAxisValue, it will return you 0. So you'll lose the information of what appened at t1...