JMHO,.....
3.6's are every bit as good as a 3.2,
IF they are properly spec'ed & assembled. Its all about the attention to details and using the proper components based on how the engine will be used. In some cases, building a high-powered 3.6 can cost more money, but thats dependent on the application. Reliability & durability are both excellent provided the correct components are chosen and installed correctly.
In the context of street usage, both engines are very good performers, with the nod to the 3.6 simply based on torque. "There is no replacement for displacement" insofar as street motors go,....