I have tested a S.T. Dupont Elysée in F. The nib is very smooth and it offers a slight variation (up to M). Otherwise, I have 3 S.T. Dupont: a Classique, a Fidélio, a Défi, and a couple of ballpoints (2 Classique from different periods, and a gold plated Fidelio). I offered a Liberty ballpoint to my girlfriend. I'm thinking about buying an Elysée too.
As far as I'm concerned, they are all of exquisite quality.
It's my opinion, but compared to Montblanc, Dupont offers more than plastic for the body, for a far better price, and the nibs (which they also make themselves) are of comparable quality and smoothness.
I don't know about the aftersales service: I never had to use it
(and I think that's good like this).
Edited by olivier78860, 08 June 2012 - 14:02.