I went for the Border CV-W in the end John, I wasn't particularly looking for speed as I'll be shooting them indoors. Torsional stability, straightness and general build quality were my main requirements. In your experience does Wood core or Synthetic core have the best torsional stability?The reality is that the core material of the limb has no effect at all on the draw force curve. That's all down to the working part of the limb. So anyone who reports a synthetic core limb feeling different on the draw to a wood core limb is either reading in their own bias, or detecting small differences in the geometry of the limbs.
The core material affects the limb speed - lighter is faster - and possibly the susceptibility to temperature change. That's it really.