The Celestion-Truvox-0820 looks like a direct upgrade to the HT-8 drivers (barring crossover changes that may be needed) and they're coming in at the same price (for now) as the old Celestion TF0818-8. 2-3db more sensitivity, 2db more power handling, 5mm xmax vs 3.25mm xmax. All pure upgrades, I checked the sensitivity based on the graph, not the number listed.