Nice review. Your comments on the depth and intensity of the colour are spot on. My other coloured demonstrators (eg the Pelikan M200 blue) look pale and dingy compared to my Chartres and Bourgogne.
Like several other contributors I found some of the 3776 nibs can be a bit too scratchy out of the box and the micromesh and brown paper bag have been used on most of mine. I've also found a couple of the 3776s in my possession wrote a little too dry for my taste - however I should say I got them second hand, so that may be down to previous owners' use/tastes.