In my experience, those who slag Fiat off and Stilo's in particular haven't owned one. Yes they have problems but no worse than many and a lot better than some so called premium brands. Check out the Warrenty direct website for their car reliability index. Last time I looked it was Alfa, Saab and Audi at the bottom.
www.reliabilityindex.co.uk/trends4.html?apc=3128339010848601
2003 Index (in the middle of the stilo model's lifespan) says Fiat were 9th from 23 marques, beating Audi's, Merc's, Volvo's, Bimmers & Saab's.
Interesting site, well worth a browse!