Just a quick update... the Aveo is still going strong! Not sure exactly how many miles he has put on it since... will have to ask... but he is still impressed with the fuel economy.
On a side note... I purchased another Aveo a few weeks ago with the same shattered idler pulley problem... replaced all the valves/guides/seals/etc and she runs! I must be a glutton for punishment... but after doing it once the second time went much faster.