Thats only 8-12 damage for each vampire AND they're more expensive than daggers upped or unupped. This idea fails hard unless its upped.
It certainly doesn't perform up to the standards of the upped version, nor should it.
Here's the thing...it's still fun to play and it DOES work, albeit not as well. But it works well enough, it wins fast enough and often enough to suit me. That said, I don't really grind. It's unusual for me to play for more than half an hour a day, at most. My most important consideration is..."Does this strategy and associated configuration entertain me?"
The answer is yes...along with the Fractal Vampire/Devourer deck, and the Parasitic Voodoo deck. I made...all unupped because I don't have the coin to up any cards, nor am I really in a hurry to do so.
So I fail to see how the deck "fails hard" when it does what it's supposed to within its own limitations, still fulfilling its concept, and more importantly is enjoyable to play.
Edit: On another note, if I get my hands on more Stilettos, I might well buy Flying Weapon cards and up them as I can. They're the only card that MUST be in its upped form, since then it's still merely a duo deck instead of a trio.