I've had my 2001 year 156 2.0TS for about 10 months. In that time it's had the starter motor replaced under warranty (it was squealing), 48K service (£175), 4 new tyres (eagle F1's at 'cost' price £240), cambelts and variator (warranty paid for variator and labour, I paid for parts £250).
The service and tyres are normal running costs, the cambelts were due anyway and I managed to wangle the variator out of the warranty company as it has just started making some rattling. I have since heard that the starter motor squeal could have been cured by simply cleaning it out.
I have not spent anything on the car since early Jan, when the belts were done.
Fuel consumption varies, but I usually get around 30mpg in mixed driving (got 370 miles out of the last tank).
All in all I am pretty pleased so far, much much more reliable than my old 145QV.
I would not be too paranoid, just keep an eye on the oil level and ensure the belts have been changed aporrox every 36,000.