First of all you can order any fletching tool you feel more comfortable with either left or right from a catalog, or on the net.
I've asked the same question at the three nearest pro shops to me and got the same answer: "doesn't matter, just make sure your broadheads are nice and snug." I've read the same thing in books and magazine articles.
I happen to use right because thats the tool I have.

"Hunt smart, know your target and beyond"