2.5 engines had issues with cylinder liners, rear main oil seal will fail.
Then also they also have IMS bearing issue as well
Let's then see coolant issues of water pump failure and even causing the heads to crack on extreme yes but usually if a coolant system fails the engine gets hot very quick so there is that do worry about also
Let's continue shall we , they can also be known to crack exhaust manifolds, depending on the wheels they get very bad corrosion like the Toyota wheels or the GM chrome SUV wheels.
Now by no stretch at i saying a z3 doesn't have its own issues either but they are much easier to deal with and handle