rodstewartlukas: I think denon is better than marantz, because i have heard that denon bought 70% marantz stocks. Its so hard to choose, because i am going to buy amp from internet, so i cant listen at hifi shop. I like all music styles except metal, hard rock. Thanks for answers.
Denon and Marantz are now owned by the same company, but don't let this lead you into believing one is better than the other purely based in this fact. Both companies still produce their products in the same they they always have, and there will be differences between them.
Personally I'm not big on Denon amplification, but they produce some good value for money budget stuff. I would prefer the Marantz as far as sound quality goes.
Beware of the MF suggestion - for me the A5 is a big powerful ball of boring mush, with no heart or sense of musicality. This goes to show how opinions can differ on a single product - you really need to hear for yourself with your own speakers.