I'm planning on going FX with a D700 in the next few months, and considering the fact that I shoot a lot of indoor ice hockey (my son's team) I will lose the DX multiplication factor with my current lenses. I'm looking at getting a teleconverter to replace the reach, but wondering if I should get the TC-14E or the TC-17E? I'm aware that the TC-14E will increase my 70-200 VR f2.8 to a f4.0, but will the TC-17E make it a f5.6 since it increases the f-stop by 1.5? A f-stop of 5.6 is too slow (I think) for what I'm shooting without flash considering the D700's better ISO/low noise capability. What is the Cafe's input? TIA for your input.