Bearprint: [1] how long in percentage these are to each other when you factor in all 4 campaigns? Like, 25, 25, 25, 25?
[2] Does the "DLC" have (new) music and stuff? There is a 3rd DLC in Calfree.net for Hong Kong which is music, how is that? Is the DLC really better than the main game?
[3] Is there additional DLC worh mentioning for the series? (I have all games)
[1] The main
Hong Kong campaign is quite long. The extra is probably less than half (I have only played through it once, so far) but it is much, much harder. (Most enemies have weapons that stun.)
Each of @Cirion's
UGC (see third point, below) is similar in length to the official games.
(But see discussion
here.)
These games are all very combat-intensive, so you will need a competent fighter or else face a lot of frustration, even on easy. (A mage works well.)
[2] The DLC recommended for
CalFree is from a third-party; it restores the music from
Dragonfall, which a lot of people think is far superior to the
HK music. (I am one.)
It is a straight swap, for the most part, so mood is matched (there is music for "action" and "exploration",
etc.) with the single exception of a new vocal song (which I think is terrific, but YMMD) that is used for battles, from the band
Invocation Array.
[3] It is a trilogy. They are all excellent, made by someone who played the tabletop games in the eighties and is an expert on the background lore.
The first is
Antumbra. (It was built for the first Harebrained release,
Shadowrun Returns, but works equally well in any of the games.) The end bosses can be difficult so you might want to reduce the difficulty for them. (This entire mod was actually three smaller mods that were combined.)
My favourite is
The Caldecott Caper. (It was built for
Dragonfall, but was updated to run in the
HK engine.)
edit: only one gorram hyperlink per paragraph.