[jedimaster]

1st: FC/Late DS9 (and the matching dress uni) they were a good balance between the futuristic style we came to expect and a more military look.
2nd: ENT, great balance between current military and the future, as well as the most practical.
3rd: TWoK Classical military styling, good for formal functions but not everyday.

In response to comments on the uniforms seen on AR-558, the novels expand on these calling them Surface Operations Blacks (convenient acronym, there). Elias Vaughn also mention that they have energy and shrapnel dispersal layers and that the coloured yoke has been removed for exactly the reason stated earlier, to prevent a units command officers being picked off.