I have the ZPD Delica (original light blue handled one) and the ZPD Caly III and the Delica was a disappointment as a slicer. The Caly Jr is supposed to be one of the best slicers but the Caly III is right up there with it. If you like the cutting/slicing ability of the Caly Jr I would get a CF ZPD Caly III over the Delica. It is more expensive however it makes for a dressier option than your Jr. A man has to have options in the morning.
-Mat
+1, I'm a Calypso guy, have 2 grey FRN/VG-10 Jrs, 1 black ZDP-189 Jr, 1 G10/VG-10 SE Caly III, and a CF/ZDP-189 Caly III, (and a UKPK, too), it gives me many options when I get dressed.
Going to Paris? Don't want to have too much problems with cops, UKPK
Going to sweat a lot? VG-10 Calypso Jr
Normal day? ZDP-189 Caly Jr or Caly III
I don't use the SE Caly III at all, though, since I recieved a cricket at the same time and it packs a wicked SE and edge profile in an even more compact package. (added to the fact I rarely need a SE knife)
If you can afford the G-10/VG-10 version but not the CF/ZDP-189 version, just take the first one, it's still a very nice knife and it may look better than the Jr as a dress knife.
If you want to have a sturdier knife for about the same size, though, the Delica fits the bill nicely, but it handles very differently. If you already have a Delica and like it, then take the ZDP version, if you have never handled one, try one in a shop, and see if it fits your hand well or not. (It doesn't fit mine well, for instance, the handle seems too short for a comfortable grip. It totally depends on whose hand it's in, though, YMMV)