A few questions:
How does the density of fiberglass compare with aluminum? I've tried looking this up but I don't exactly know what type of fiberglass I'm looking for anyways

. I mean, .80lb/ft^3 probably means I'm looking at an insulator, not a structural material :-P.
Also, how much does fiberglass cost usually? I would check McMaster, but I'm not exactly sure what I'm looking for.
How good is the 20mmX20mm that Item sells? Are the fasteners better or worse, in your opinion, than Bosch, in terms of durability and utility?
Thanks,
Shrenik