The 3.2 has a Holden Alloytec engine. Engines manufactured after mid-2007 have an improved chain, so mainly only earlier Alfa 159/Brera models are affected.
This from Holden service manual regarding these timing chains:
There was an issue with the timing chain manufacturing process that caused, in a small number of engines, the chain links to be outside design specifications, which over time, may result in chain elongation.
The degree of chain elongation will depend on the number of affected links and the drive cycle of the engine during its life. Typical expectation is that ECM detectable chain elongation would only occur in early engine life. i.e. 10,000km to 20,000km.
CORRECTION – Vehicle Production
Improved timing chains were introduced from the following breakpoint:
Engine Number : Eng Built Date:
The oil temperature sensor and the steering rack are two areas to watch. Tyre wear can be high without proper alignment.
The engines are generally reliable with proper maintenance but, as pointed out, it's prudent to have oil changes more frequently than the owner's manual stipulates.