The Marantz "house sound" leans toward slightly warm. Oppo is more neutral. I have a Marantz 7704 and before that an 8801. The 7704 has been bulletproof so far and sounds great for home theater. I've also owned Marantz CD players including the KI-Pearl.
They were anything but harsh. If anything, they were not great at detail retrieval, much like the Oppo, which is a jack of all trades and master of none. Once you compare a decent disc spinner to an Oppo you'll realize that it is very middle of the road.
In short, if a person is happy with the sound quality of an Oppo and wants a HT processor that is easy to listen to and not "thin" sounding, then Marantz should fit the bill.
They don't appear to have any at the moment, but if you keep an eye on accessories4less they often have factory refurbished units at a significant discount that come with a 3 year warranty.