It does seem the Air Conditioning on the Aero is really very robust.
Mine stopped working, it is now almost 9 years old, so I passed the problem to Williams.
It turned out that the system was very low on gas, so a complete refill solved the problem, it is now almost arctic!
They suggested that the system needs checking every 3 years... even with no leaks the fas does diffuse through the rubber hoses.
So, if your A/C isn't blowing cold, get it checked.