Problems with vampires: 1) They will accuse other dwarfs of being vampire 2) They can't feed from other vampires, so at some point vampires will outnumber regular dwarfs and even new migrants can't help in that. So that will result vampires suffering from lack of drinking 3) Wouldn't they still pretend to be vampires even when whole fortress is full of them? So they would still move as slowly as regular dwarfs.
Did Toady intentionally make it so Vampires are like The Thing?
I hope everyones wrong about vampires and they are a dangerous thing to have around,
Other wise, Normal dwarves will just end up being cattle for Elite dwarves [vampires]
Which does not please me.
As noted previously:
1) Vampires can't increase their skills
2) Vampires can kill your legendary normal dwarves
3) Forts with lots of vampires will eventually deplete your population of normal dwarves, thus running out of food
4) IIRC, vampires that haven't drunk in a while won't die, but rather get significant stat and skill penalties.
5) The particular strain of vampires infesting your fort may be vulnerable to a material commonly used by your enemies.