I had the Onkyo 503 (an earlier version of the 506 only rated at 75 watts x 7 channels) driving my m22's in a room slightly larger than yours and had no problems driving them to high slp cleanly. The 606 should have no problems with any of your choices since you are driving an 8 ohm load with all of your choices and Axiom's are all have high sensitivity. I liked my Onkyo so much that I replaced with the Onkyo 805 about a month ago so that I could enjoy the new audio codecs. There isn't much competition with Onkyo if you just have to drive 6 or 8 ohm speakers due to all of the features that they pack into such a reasonable price.
- Nick
