Depends on the Mythos (and in some the individual Valmpire, but I don't feel so. They can't help needing to drink blood, my definition of Evil would have to enclude drawing enjoyment from the suffering.
But then I guess it also depends on your definition of Evil; if yours simply covered hurting humans, regardless of needs or reasons then every Vampire is evil, but then so are Mosquitoes. And what of people who would willingly let Vampires drink from them? Would a Vampire feeding off these people be considered Evil, even under that definition?
Personally, I like my Vampire stories about the sexual predator, where the Vampires are almost perfect killing machines; sexual attraction being able to draw humans out from the heard and superhuman physical abilities allowing them to subdue, feed and likely eventually kill them. I like the stories where, although humans feel unbearable lust looking at Vampires, they feel nothing for us, seeing us as weak, almost undeserving of life, only tolerated as food. That to me is a "proper" Vampire, different to some of the origional stories but one that I feel fits into both a modern world and a horror story. And these Vampires, they're no more evil than the farmer snapping the necks of chickens.