There is not enough difference in power to make it a real concern, I would look more into features you desire and other issues such as ease, remote, set-up. If you trust your dealers opinion then go with Integra, both have XM ready radio service, HDMI 1.1, and MM Phono.
I think Integra is better in that it supports Dolby 7.1ES while Denon doesnt in that model. Also the INtegra has up to 240 watts per channel of dynamic power in the front 2 channels so it can handle more then it looks like on paper.
Having owned the Onkyo (Integra) products and being familiar with friends Denon units.....I would go Integra.
I think Integra is better in that it supports Dolby 7.1ES while Denon doesnt in that model. Also the INtegra has up to 240 watts per channel of dynamic power in the front 2 channels so it can handle more then it looks like on paper.
Having owned the Onkyo (Integra) products and being familiar with friends Denon units.....I would go Integra.