Unless a specific receiver is 'voiced' differently than others (meaning it intentionally alters some frequencies relative to others) there is NO difference between comparable receivers other than their ability to drive difficult loads like low impedance speakers.
If you have experience with Marantz and have been generally satisfied with their performance, then buy another Marantz. That is exactly how each of us has developed a brand preference over the years - experience. If you were to subject yourself to a welll designed double blind test, you will not be able to pick one over the other unless one is accurate and the other purposely deviates from a flat response.
Don't rock the boat. If you like Marantz, stick with it.