I went through the same quandry appox 3 months ago. Did a little research found that the preamp/processer in the 305/307 is the reference 30. Check the stats on the power amps in the recievers 150/channel, by the time you make your best deal on the reciever the power amps are little to no cost. I bought the 305 had a extra 2 channel power amp and now enjoy 7 channels of rich HT and Great DVD AUDIO
