What Woodcraft says about their Pfeil "Veiners" : "These gouges are more 'U' shaped than any other sweep. They are well suited to fluting and preliminary outlining of relief carvings. Their shape allows them to make a clean, deep cut in one pass without fear of the corners of the tool digging in."
What they say about their "V-parting tools": "Are forged and precision ground with straight sides and vee bottom edge. Principal uses include outlining, rounding over edges with the straight side, adding detail, textures to backgrounds, undercutting, and applying decoration in chip carving."
I like the .5mm veiner for outlining.
So as the old umpire story goes:
Umpire # 1: "I am the best umpire cause I call them the way they are!"
Umpire # 2: "I am the best umpire cause I call them the way I see them!"
Then Ol' Acer said: I am the best umpire cause they are nothing until I call them!!