Ive got a 53 plate. that age had the old style EGR valve which was prone to sticking and any car that had it replaced would have had the old replacement unless after about mar 06.
I have the 2.0 tdci and its generally a good car, roomy and i get good fuel consuption, though it does get bad when due a service, but i average 45-48mpg.
Cars are coming down in price, ive been offered about 6k for mine part ex but it is the ghia, with leather and dvd.