When I originally bought this reciever, I thought I would use it as a pre-pro and use external amps eventually. It has been several years now and I still am using the reciever only and am content with the results. There just doesn't seem to be a lot going on with most recordings in the rear speakers of surround to warrant a huge amount of power to drive them, at least in my experience.
If it helps, when I bought my reciever, Kal Rubinson was reviewing the 4806 in Stereophile magazine and he had some useful insights into the strengths and weaknesses of the unit. This is one article
http://stereophile.com/musicintheround/306mitr/index.html I know there is an earlier article, but I can't remember the month. This was the better article of the two.
Towards the end of the article, Kal compares the onboard amps of the Denon with his Bryston 9B-ST amp in a positive light
