Pistoleer Archive

I just recently got this skill. It seems to work very well. My first question is, does it work against high level creatures?

My question question concerns PvP. I used it and it worked too well. As long as I got the hit in, I would kill the guy b/c he could never get a move in. It seems cheap, though I admit it's balanced by the fact the riflemen can kill me with one shot. How does one defend against this move? Do you just have to get high enough skill to get the +20 defense against knockdown?