I agree with
@everettT on that point. With 80w into 2 channels, you are well over what would be considered reference level dynamic peaks. And even as Klipsch is known to fudge their sensitivity, even at 90db sensitivity, your 2-channel listening would still clear those dynamic peaks.
Personally, I like having my amps, even though I might not ever really use them: but my speakers are in the 85 and 86dB range, so for me, I need ~128w to clear that same dynamic range, which is probably more than my marantz can do, even considering that real-world power is way different than the RMS ratings.