what does it matter anyway?
surely you can afford a full carbon fibre pole and if it lasts 2 years you ve got your moneys worth.with these new clamps that alex is bringing out i bet the carbon poles will be lasting more like 3 or 4 years before needing replacing.
your wasting your time with anything other than full carbon fibre as they are more rigid and lighter making your working day easier and more productive.
regards
dazmond