Here is a side by side comparison between the two.
I replaced mine very much earlier when the workshop have the aluminium ones.
The temp reading on the dash is not really accurate imo because i have installed a temp guage and whether the water is 90deg or hitting 110+ deg on a track - the needle on the dash always stayed in the same position.
The coolant for aveo should never need much topping up unless u have a crack in the tank like i had before, so overheating is very unlikely.
![Image](http://www.rdyautocare.com/images/thermostat_hosuing_compare.JPG)
I also have the internal modified so the coolant always flowed regardless of the coolant temp.