2.4 OR 1.9 JTD - HEART OR HEAD?

[correlejco]

OK - so I've given up on the idea of the Jaguar 2.2D or the Beemer. I'll stick with quirky Alfas to go along with my wife's 2.0TS 156 and the son's Spider.

I need the economy of the diesel, so it's a facelift (2004) 156 JTD. But should I go for the 20v 2.4 (heart) or 1.9 (head)? I know the 2.4 sounds good and goes (a bit) better - but will I get significantly better mpg from the 1.9? And is the 2.4 really much quicker?

I need sound, sober advice (which ideally tells me to get the 2.4)