Well, I agree to take no chance with the Brakes. But waiting till reduced braking efficiency is dangerous. And normally it is vice versa: Squeaking starts first; after many days only you feel loss of braking efficiency, no? After hearing the first 'crying', Brake will work perfectly for many days, if not months. (of course at the cost of drum, hence not advisable to wait). So, if time permits, check Brakes periodically, or be very attentive to the first cry, change it immediately. (For me the later alone is possible, time...). In my 25 year driving exp. once or twice only I had to change drum, that too at the 5th year on my Esteem and 8th year on my Indica. But best is checking periodically, I agree firmly.