I have heard that said a few times, Then just the oposite. Myself, I just don't hear that at all. Also, many times a few people have said the Axiom's are "bright", then a ton of people say NO, they are not, so go figure. Like I said it's very subjective. I have been told I have an overly critical ear - perfectionist, as It just took 4 hours of convincing to my wife to "allow" me to put up some acoustic panels, (the best looking ones I could find ASC vertical beech frame panals, contoured with black cloth) that being said, I would descibe the sound as rich, and detailed, very smooth, I think the Yamaha works wonderfully with the 60s. And it will takes you weeks to discover all the functions. I would head to your local A/V place, Not the circut city type, and audition the various receivers, Harmon, NAD, Denon, Pioneer, Onkyo, and see what YOUR PERSONAL preference is. Try not to listen to the salesman, but your ears, and feelings. I think "bright" or any other overage of sound is more determined by the speaker, there are many great receivers out there, it just depends on what you want it to do, the Yamaha will sound great, so will others.
