Depends what you're using it for.
Is it a family ca, will you need plenty of seat/boot room??
I've a 308 (just under 2 years old) and it's ideal for me - I'm a window cleaner - good size boot (it's an estate) and good mpg and low tax ... but you'll prob know all that already, seeing as you've got one at the mo :)
I suppose f you've had a bad experience with a certain make of car, it'll put you off ....
I've only had my 308 for a few months .... so far so good.
My last car was a Peugeot 307 - had that for 9 years .... it never let me down ;)
Giz, the Peugeot that I owned ( as a second car ) was a 307, I've never had so many things go wrong on a car before and all of the problems was electrical.
Agree with Zacs. My last six cars have been Volvos. They have tremendous customer loyalty - somewhere in the region of 80% of people buying new Volvos are presently Volvo owners.