How is the edge support and cooling?

Both are strengths. Edge support scores an excellent 9.0: the pocketed-coil system carries firm support out to the perimeter, so sitting on the side or sleeping near the edge feels stable with little roll-off, better than most hybrids in its class. Cooling scores 8.6, with surface temperature settling around 30 C, because air moves through the open coil core instead of being trapped in a solid foam slab.