I have respect for some of the Avalon offerings, much more than for most audio companies. But the Eidolon Diamonds compared to the Revel in terms of musicality? What can your contact be talking about?
If by musicality we mean ease of listening, richness of real instruments, tonal ease, then he is giving you real bad advice. The Avalons have more detail, but I should call that "apparent detail"....so much richness is stripped away that this alone would make any speaker more detailed.
If you want a magnifying glass that will amplify every little detail and wart, and if you don't have ears that are sensitive to brightness range highlighting, you may want to consider them. If you find that many high end speakers are too tweeter-prominent, be careful.
The Revels, meanwhile, are pretty much right down the center. Not artifically thick, not thin, nicely detailed but nicely natural too.