Roll-top dry packs are not designed to be submerged - if the closure is held under water deep enough/long enough water will seep through the closure. The Hydraulic Pro Duffle has a watertight zipper and can be submerged. 

A freestanding tent has poles that extend down to all internal four corners, holding them under tension. A semi-freestanding tent has poles that extend down to two corners, but two other corners need to be staked out to provide tension. Semi-freestanding tents are lighter than freestanding models.

If you consider weight, heat conduction & durability, the best cookware material is a quality hard-anodized aluminum alloy. Stainless steel and titanium are stronger but heavier / less heat conductive. Good engineering can make aluminum cookware perfectly strong enough.

Wash out Watercells / Pack Taps using warm (not hot) water and dish soap, and rinse thoroughly. Effervescent peroxide tablets will remove harder-to-clean residue. Store hanging up (upside down) with the cap removed.