Best sounding mid reciever -temp replace separates

Marantz is fine. I just think Denon and Onkyo have the best combination of performance and user friendliness of all the current offerings.

For Marantz, I suggest SR7002 THX® Select2 Surround Receiver

For Yamaha, I suggest RX-V1900 7.1 Channel Home Theater Receiver

Again, these are all great sounding for what they are - basically 7 amps in a box. Buy the one that looks the best on your shelf, has the most desired features or layout, cost the least or is most compatible with your current remote.

Cambridge Audio may fit your needs. Great sound and build.

what are the speakers you're using and what about the room?

I am using sonus faber concerto's ,piccolo center and walls as surrounds -listeneing about 12' from the front speakers