Question??? If you place the model on the balancer lets say in a slight tail down position and it holds that position, then try it with a slight nose down position..........if it stays in that position as well and then holds steady when set in a level position you then have a perfectly balanced model.

Most people forget that a model in perfect balance will hold it's position as described above. I have nothing but giant scale models and I try to get to this level of balance for the first flight. I then fly the plane for a few flights to see if I would like to make changes to the CG to get the plane to fly or handel a bit different.

However if you cannot acheive this condition for whatever reason then my suggestion is to balance a bit nose heavy.....a bit tail heavy will make the model very touchy and may cause you loss of control if your flying skills are less than very very good ( like mine it seems sometimes) A slight nose heavy model will be much eaiser to control till you can get it back down to fix the CG if you don't like the way it flys.

Hope this helps you somewhat.
Good Luck!!!!