Hello, I have some experience myself with the Arcam AVR280. I have changed receiver several times trying to improve the musicality of the system. I had a Denon 1602 then an Onkyo 701E and now an Arcam AVR280. When I decided to go for the Arcam, it was based on the reviews from most specialized magazines which claimed this to be one of the most musical receivers. I have had this for almost one year now and I am quite happy but I still think that it does not provide the same quality for music as you would get from a separate stereo amp. At the beggining I had the Arcam paired with B&W 685 but one day I tried with my old Wharfedale 9.1. and found that I enjoyed the music more so, I left it with the Wharfedale 9.1. It seems that this amp works better with smaller speakers that have lots of clarity and not so much bass. The B&W 685 had too much bass for the Arcam and sounded muded.
I wrote to a magazine in Spain some months ago and questioned the musicallity of the Arcam AVR280 saying that I did not noticed such huge improvement vs my old Onkyo. Their reply was "We are sorry to hear that you are not happy with this receiver because it is one of the few receivers in this price range that provides outstanding sound with both movies and music". If this is the reply from a specialiced magazine then my possition now is basically to accept that it is not worth it to continue trying to get better stereo performance from an AV receiver. Unless things change dramatically and companies start to finally understand that what we need is real quality stereo sound in the receivers instead of bells and whisels then it is not worth it to change. Based on my experience I could only recomend to change to a stereo amp for music and a budget amp for movies.
Saludos.