Marantz Pm 6004 ?

Hi.I have a Marantz stereo reciever at the moment the SR 5023 http://www.marantz.co.uk/uk/Products/Pages/ProductDetails.aspx?CatId=hif... And I was wondering if I would benefit anything sound quality wise by changing it for a dedicated amp PM6004.They are both styled in the same design so would compliment each other.I wonder if someone a bit more technically minded could weigh up the specs between the two and ad vise me.The reciever is a lot more powerful than the PM 6004 but that is not everything its sound quality that I am trying to improve.Any advise will be gladly recieved.Cheers