Way too rich for me at $24K. I think the Ref 5 (@ $12K) is plenty upgrade for me from my Ref 3. I bought all my current equipment brand new. This time around I will wait for a lightly used Ref 5 before I upgrade. The Ref 5 is starting to accumulate positive reviews. The most relevant for me is from Hifi Critic (which is a UK publication that does not take any advertising and seems to have very thorough reviewing protocols - both qualitative and measurement protocols) which gave the Ref 5 an unequivocal rave review (you can find ARC reviews here for those interested:
Audio Research Product Reviews). I am sure this special Anniversary edition at twice the cost, and with the over-engineered power supply in the separate chassis and even more premium parts, will deliver even better performance, but I have to believe the law of diminishing returns here has to start becoming more meaningful at this point.