Can anybody tell me the difference in charactoristics between iron shafts dynamic gold r300 regular and the kbs tour v 90 in stiff? I have the ap2s 714 with the DG r300s in but they are a little weak for me. Iv had a quick fitting with 2 pros that have fitted i think a miz gadget that attaches to my shafts. Both times it came up that I should be using the kbs tour v 90g in stiff but is their a big difference between the 2 different shafts and my reg r300 shaft to a stiff in the kbs? Thanks.