I think that might be down to the fact that whenever you talk most hi end dealers about Denon they automatically see them at the same level as their cheaper AVR's or Mini systems made in either china or Vietnam, But, Like Marantz, their top tier and better quality models are designed and built in Japan like the PMA1600/1700NE and the PMA2500 series, I don't think many dealers realize the top end Denon's are serious Hi Fi and are as good as any lower end Naim, Rega, Roksan, Musical Fidelity, & Audiolab products so they tend not to recommend them as much as those British amps or even the mid range Marantz amps.
Just the other day I was at the Audio Barn (who sell mainly high end gear) I was after listening to some ATC smc19's, when he asked me what amp I had, I told him it was the Denon PMA1600ne and straight away he dissed the Denon as if it was cheap rubbish and that I should immediately upgrade it to a 60 w per ch Naim Nait 5si because my Denon wouldn't be able to drive them properly, I reminded him that my Denon amp was able to output 140w into 4 ohms and has a sizable power supply with high current capabilities, weighed in at nearly 40 lbs and was reviewed and tested by David Vivian from Hi-Fi Choice magazine and actually WON the group test bettering strong competitors from Arcam, Hegel, NAD, Technics and Yamaha. The look on his face said everything so I didn't even bother to stick around.
I Got exactly the same response from Sevenoaks sav. These guys need to get with it, and realize that the top end models from Denon and Marantz are just as capable as amplifiers made in the UK, I know this as I had already tried a Naim Nait 5si and a Rega Elex-R before I bought the Denon and for me the Denon sounded better than both of those. They don't even stock the Denon or Marantz so they are not even on their Radar, either way their ignorance is quite off putting, ..and then whatever you do, don't mention you want tone controls or they'll show you the door.