I dont work for chev I got all my vechile traing from my brother got his own garge when I was still in school and millitary training.
I agree with you unfortuned nobody give a warrenty / garantee on how long their belt can last. My second belt broke after 3000km lucky for me when it idle.So if there is a manufaturer to give the garantee for 100.000 I will buy that belt and pay little more. When opening the the top cover of the belt you can check how much the belt work if you look the outside will be shiny showing where the teeth are and on the inside tooth busy to pull apart. With my car I did find the cam belt sprocket on the grankshaft has worn aswell on the teeth and the keyway worn meaning your timing marks move.
When my car was still under warranty before every service I mark all components thats needed to be replace reason they check and adjust spark plugs, I put on a fight to get my spares replaced.
If they did design the motor with a timming chain that would have been excellent.
But help me if I am wrong Chev bougth out DAYWOO thats where the AVEO came from Chielo