I've had a few of each ... an Onkyo TXDS797THX receiver and a Sony STRDB 1070, not an ES, but close. The Onk was better, much more powerful and more musical, though the Sony did have superior SLAM, some aspect of attack.
I now have a Sony TA E9000ES processor in one system, and an Integra DTC 9.4 processor in another. I picked up the Sony from ebay, new B stock for $499, the Integra was about 3 times the price. Don't get me wrong, the Integra is great, extremely musical, and is a 7 channel unit with multichannel inputs and great DACS for each, but the TA E9000ES with the firmware upgrades is a match for the Integra.
My advice ... if you don't need 7 channels and don't have SACD/DVD Audio, grab a nice TA E9000ES processor, and get yourself some great used 2 channel amps. (Onkyo, Integra, Marantz, Yamaha M-80/M-85, Parasound, etc.)
