I just both one of those.
And if you realy means, when you said that "Denon will be at the top of my list when I buy my next one." i gotta tell you something important: the subwoofer pre outs cannot be used to conect an amplifier.
I dont have money for upgrades and i just need an update software, but the guys of the Denon Support home page just send me this fantastic email:
Response Via Email (NJ Customer Service & Support) 05/29/2015 08:18 AM
Hi ******,
The sub pre out is designed for connecting a powered subwoofer. You would need a receiver like the AVR-X3100W or higher which provides a full set of main zone pre outs to connect an external amplifier to. The AVR-S700W does not allow for this kind of connection.
Thank you,
Technical Support/Custom Install
D+M Group
Question Reference #150528-000469