These systems are great, pretty much plug and play and if you get the proper radio, you retain everything. In some models you can go as far as viewing tire pressure on the radio with the aftermarket radio.You have a whole lot of research on this 1 ..
Start with the authorized dealer of the Maestro RR ..
the other thing that you are assuming is that you would be replacing the Cd, XM radio mylink canbus and the analog buttons that control those signals for the particular functions .. so what interface will give you those functions if you remove them ? Good Luck ....
You do not just purchase the Maestro though, you need the wiring harness for the car as well. This is what ties into the cars wires and plugs into the Maestro.
As far as I know though, it doesn't work on the Cruze yet. You can view the compatible cars on Idatalink.