If there is no real discernible difference between an AVR and a pre/amp configuration, and the latter is considerably more expensive, what would be the argument to buy the latter?? I get the bragging rights, but for logical people with a sense of value, what would be the argument?
Well, ideally, speakers are chosen with careful consideration of local acoustics and listening habits, which will in turn dictate requisite amplification, such that you arrive as close to optimal performance right out of the gate, before any processing or eq is applied. At that point, you have the speaker/room/amp problem thoroughly addressed, or at least optimized so very little if any eq or 'room correction' processing is required. The basic requirements for the amps won't change until you change speakers, switch to a larger room, or move to a new house.
Basically, amps last a long time and really don't require changing, where processing, formats, and features will evolve at a relatively rapid pace.