THX certification, torodial transformers, somepoeople beleive that the receivered weight is a indication of its prowess. I remember looking at headroom figures at one point or if the wattage doubles when going from 8 to 4 ohm loads.

However, none of this is any indication of how good the speakers will sound in the end. Sigh...I could AB the whole range to hear which one I like the best.