Just saw this thread, and thought I might add something about comparing different weaves. I made up some test strips using 1/8" corecell, about 2cm by 20cm, with three different types of cloth I had around. I was mostly interested in stiffness. They were glassed on both sides with 1 layer.
I was comparing 12oz bi-axial E-glass, 8.9ox fine weave S-glass (style 6781), and a 7.3 oz mostly unidirectional E-glass with about 90% of the fibers aligned with the axial direction (style 7715). Stiffness was simply judged by flexing the strips by hand. The 7.3oz unidirectional E beat out the 8.9 oz S, and the 12 oz bi-ax came in last. I expected that in this direction the 7715 would beat the slightly heavier S, but was not as sure what to expect from the bi-axial heavier stuff.
Of course this does not measure impact resistance, I expect the resuls would be opposite.
As for torsion, the 7715 still feels stiffer than the S, but I think the bi-ax might take that, but hard to tell. I think torsion is huge for snowboard building, but with tapered tips on a typical twin tip, I don't expect torsional stiffness is nearly as noticable.
For what we are building where much more strength is needed in the long axis, it's worth exploring the different weaves like tri-ax and unidirectional, and not just different cloths like E, S and carbon. You might find good strength vs weight vs cost without having to go to carbon.
Peter