Here is the thing,
Pace if accurate and used properly, can blow away an opposition regardless of the conditions. We have seen Waqar, Shoaib, Lee, Tait, Steyn (he can also do that with swing though) do that..
On the other hand, swing or seam, if the conditions are conducive is extremely difficult too. When there is help from the pitch, even Irfan Pathan gets a hatrick and bowls like an Akram.
But if the conditions are not conducive, then it becomes a lot easier to face the same swing/seam bowler. However, a bowler just wiht sheer pace can still be threatening on a flat pitch. Doesn't happen always, but it is possible.