I had the petrol version for 6 years (67,000 miles) from new.
I also had the propshaft bearing failure, a known weak point on this car, There is a thread on here about bearing replacement, which is a cheaper option compared to replacing the entire shaft as I did.
I also had an ABS fault that showed up as a rear wheel sensor. Since I sold the car (with the error) I read a thread that said there is a connector in the loom that can be cleaned a should resolve the issue.
I believe that the water in the boot can come in from a rubber seal on the boot door handle, whilst mine was showing signs of age, it didn't get to the point where it leaked.
Those are really the only problems I had with the car, and on the whole I loved it.
They are great in bad weather (snow/ice/floods) I drove mine through a 2 foot flood with no issue.