Replying to Dynastar BT mounting points

I picked up some Big Troubles off of Getboards and I'm trying to figure out where to mount them. After looking at them I saw that near the waist of the ski it says 4,1. I assume that these are the mount points with 4 representing 4 cm forward of the waist of the ski while the 1 is for 1 cm back. I'm thinking about putting them at +2 of this point so I can still goof off in the park without sacrificing too much tip for pow days. I'd like to hear from people who have the BT's and what they think about where they are mounted.