Hi,
I had researched the Onkyo SR601 receiver a while back but ended up buying Yamaha RX-V1400. I am sure it will work very well with the Axiom speakers.
There's a detailed review of this receiver at the
Audioholics site and the reviewer used the top-of-the-line Axiom M80's when testing the receiver.
Cheers / Mahesh
PS : For a little bit more (USD 550+), you can pickup the Yamaha RX-V1400 which has YPAO (Room EQ adjustment / optimiser). This is a very good feature to have. Also the new version of RX-V1400 (just recently updated) also handles Dolby Prologic IIx.