just finished installing my RX1700 with a set of Wharfdale Diamonds. I also purchased a couple of extra diamond 8.1's to act as presence speakers. I encountered some problems however.
I decided to bi-amp my front 2 speakers to give them a bit of extra grunt and noted in the manual that when bi-amping the front speakers, you cannot use surround back speakers as it uses that channel to bi-amp. No problem - don't have any anyway. However after connecting it all up and flicking bi-amp on, i notice i can no longer run my Presence speakers either. I go through the settings and the Amp does not allow me to turn presence speakers on in the SET MENU. I go back, re-wire the speakers and turn bi-amp off and viola - the menu option for presence speakers now works.
The manual doesn't indicate that you can't run presence speakers while bi-amping, but it certainly seems to be the case. It's not a big deal, the front speakers still sound great with just the single connection, and the presence speakers add some nice clarity in the mid range.
Other than this slight set back, everything else is going great. The audio processing features on the amp are fantastic, and the only big remaining test is hooking up the brand new HTPC im building to the 60" Sony SXRD tv thats coming next week. Planning on running HDMI from the HTPC to the amp and then from the amp to the TV. The HTPC will always be putting out a 1080p connection so upscaling isn't an issue and the amp should upscale all other connections to make the TV look HOT :P
will let you know how it turns out.