I think my foundation would crack just from the weight. It would be nice to have an amp next to each speaker or maybe some Mackie's with built in amps, but I did not wire for that so no can do in this house. It wouldn't sound that much different to me and definitely not worth the money, but if someone were to give me 7 I wouldn't turn them away and might even redrywall. ^_^
I think any pre-pros from Emotiva or Outlaw will sound great.
The Parasound 7100 pre-pros has awesome specs for a pre-pros (F.R. 20Hz-20kHz +/-0.1dB, Crosstalk -105dB, SNR > 105dB, THD < 0.005%, Output Impedance 120 ohms), but it also does not have all the new surround sound codecs (TrueHD, DTS-MA) and it costs like $2K.
So I think your earliest best bet will be the Emotiva LMC-2, which is suppose to come out sometime in March for around $600 (I heard). 4 HDMI-1.3, TrueHD, DTS-MA-- it's got it all for an unbelievable price and 5 yr warranty. Knowing Emotiva, the build quality, fit & finish will also be top notch.