I guess it is down to luck and previous maintenance but the front mounts is a good call and worth checking
One thing to look out for on the 159 /Brera these days apart from everything else is the front subframe and metal bits rad mounts air filter bracket rusting away . You can't see it because of the under tray but I've seen a few now one guy decided to scrap it .
The 2.4 wasn't great in the 159 imho , I found the1.9 just nicer to drive.
As for engine I really like the 2.4 nice smooth and quick acceleration but I only get between 35 and 40 mpg but down to preference I guess