"Gonglee3":
Myself??? Ever since I was doing the home theater thing back since 2000, the only receivers that I have ever owned was Harman/Kardon and Yamaha. But I have heard some great things about Denon too.
I have owned a Harman/Kardon AVR-210 from 2000-04, and have upgraded to a Yamaha RX-V1600 in 2004. The Yamaha to me was great during it's time, and has had every conceivable feature that I can think of with exception of the current codecs that are out now (namely, Dolby TrueHD and DTS-HD as well as HDMI v1.3). During the time window I had the Yamaha, it did present a big and bold sound going through a KEF 2005.2 Speaker System/Subwoofer package.
I don't have anything bad to say about Yamaha, but I am in the process of re-doing my home theater in which I am downsizing it (but would like to retain the big and bold sound that I have grown accustomed to using a Yamaha RX-V1600/KEF 2005.2 setup..... and therefore, I am going with a Sound Bar Speaker System with a Subwoofer). I am going to go with a Polk Audio SurroundBar with a matching DSW PRO-400 Powered Subwoofer, and to drive this combo, I am going to go back to Harman/Kardon (I was going to get an AVR-247, but now, I am going to wait for the newer AVR-254 to come out next month). But like I said, I don't have anything bad to say about Yamaha. So if Yamaha is more your cup of tea, I say go for it.
As for Denon??? Like I said, I've heard nothing but great things about Denon. So, if you prefer a Denon over a Yamaha, then I am not going to pass judgement on you either way. I've never owned a Denon, so I cannot render a sound judgement or opinion to you about them.
Good Luck and Happy Shopping......
--Charles--