I finally got the RF-7 IIs in yesterday and got them hooked up. My Onkyo TX-NR809 is rated for 135 wpc while driving two channels.
I have the RF-7IIs bi-amped so four of the 809's channels are devoted to the RF-7s. I couldn't tell you if bi-amping is helpful, but j figured it couldnt hurt.
So far, I can say I really don't have any concern about volume. It gets plenty loud for my needs without even being turned up very high. It's mostly about the "quality of watt" versus the SPLs that makes me interested in amplification. I know many would say the that tubes produce what I'm looking for, but budgetarily that would not be a viable option. I suppose the tubes produce a higher "average power"?
The only reason I'm considering 300 watts is to ensure that it has the headroom to produce anything it needs at reasonable volumes.
Btw, although the Onkyo units tend to be criticized for being "non-musical", when the "Pure Audio" mode is used, it has a very clean, neutral sound. Some of the other modes that are equalized can be a bit more harsh at times.