I might be wrong but the polymer brakes are not oil filled are they? I thought they were just dust sealed? Is there different versions and a oil filled one?
They do have a larger hub mass and that could absorb some extra heat into the hub. On very steep long grades some vehicles are having engine issues due to the EGR valves recycling exhaust into inlet manifolds and constant engine braking on light commercials can be a issue.
Their extended pad change and wear profile is IMO partly larger pads, different material for pad and disc and no grit or corrosion .
"New polymer encased, fully sealed, dry brakes for top braking performance"
http://www.advancedbraking.com/sites/default/files/products/brochure/Terra_Dura.PDF
SIBS are wet brakes
" SIBS® cooling fluid is a specially selected oil which provides a path to conduct the heat from the brake disc to the housing"
http://www.advancedbraking.com/sibs-technology#how-sibs-works
