hi.. I'm going to be replacing my old sony str-d790 that I've had for about 10 years. my main criteria for the new receiver is that it have dolby 5.1, be able to drive 4 ohm speakers, have fairly good sound quality, and also be solid enough to last longer than my previous receiver. I'm leaning towards the sony DA1ES because I've heard good things about the ES line and it has the 4 ohm capability that I want without all of the extra features that I don't need. there don't seem to be a lot of reviews on this receiver, but many people have good things to say about the 2es and 4es. my question is, what are the differences between the 1es, 2es, and 4es? does the 1es have the same level of sound quality as the higher models? it seems like it would, and that the higher prices of the 2es and 4es are a result of the added channels and features. any input would be appreciated... thanks.