I'm assuming the AVR-3700H does not fit the bill as a 'flagship'?
In fact, the Onkyo is rated at 110w @ 8 ohms vs. the 3700 @ 105w...
105, 110, 150 W makes little difference. To our human ears (think log scale characteristics), going from 100 W to 150 W will get you 1.76 dB, that would be about 3 clicks on the X3700H's volume dial.
from 100 W to:
110 W.................. 0.414 dB (less than 1 click on volume)
120 W.................. 0.8 dB (less than 2 clicks)
130 W.................. 1.14 dB
so there won't be noticeable difference between 100 and 130 W but the bigger amps usually have larger power supplies and heat sinks, that could help in driving more demanding loads.
Also, when comparing power output you can't just look at the rated output in watts, but also the load conditions (e.g. the impedance of the test load), distortions, frequency dependence, and damping factor etc.