Yes, that is the biggest disadvantage - this deck inherently is responsive, meaning it will let the opponent do what he wants to do, then respond to it, while the black deck is inherently proactive, meaning it will prevent the opponent from doing anything.
Red does have the cheapest removals though, both in terms of damage and permanent destruction. So what it does, it does effectively. But the question is, is that enough?
I'm particularly looking at the green rush decks, shrieker rush decks, and poison rush decks. Despite Fractal Control being a combo deck, it doesn't win by speed. Both this deck and the black deck takes a while before it becomes unstoppable, and the rush decks can exploit that.
The creature rush deck dangers can be mitigated by getting several firestorms, but I don't know how I can deal with poison rush.