I went from offset to right helical and my groops went from 3 inches @ 35yards to 1 inch @ 35. I shoot thru a MZE so I have no problem with the fletch hitting the rest, but if you use a tm style you might have a problem. as far as right of left helical dont worry about it because the arrow starts spinning after it clears the bow, but if your broadheads are right twist go with right wing because you don`t want the broadhead competing with the fletching on steering the arrow...

Evan
Archery Accessories
301-872-0110