There are additional benefits to separates, that may or may not be audible to all listeners, such as separation of power supplies in the power and pre, less crosstalk between co-mingled audio circuitry (that's debatable), and fewer heat dissipation concerns, since you are theoretically cramming less stuff into a chassis. That being said, some of the ultra-high end integrateds avoid these issues by being large, housing power supplies in separate chassis, or using new switch mode amp topologies, which run more effifintly and therefore have fewer heat dissipation issues. I own the Musical Fidelity kW500, which is similar to the big ASR integrateds in that they offload the PSU in another box. Of course this level of design takes away two of the more obvious beneftis of integrated design - small chassis and thus lower price. To me it is worth it, but I wouldn't bet the farm that I could tell the difference between the A5 and the kW500 in a DBT...