Here's another potential option that would give you a good idea of what a modded 5900 would sound like with much less of an investment...

Denon Universal Plyr 5900 For Sale | AudiogoN

I just happened to come across this earlier today, and thought of your post. I have no affiliation with the seller. My thought is that if you bought this and it didn't meet your expectations you could easily recoup the money you spent, or you could sell your current unit if you do like the improvement that comes with the Modwright unit and probably come out close to even.

Either way keep us posted on what you decide to do.

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McIntosh MC501s, MC207, MX119 (w/TM1), LS360s, XR27, WS350s; JL Audio F113s
Denon AVR-A100; ModWright Oppo BDP-83; Bolder Squeezebox 3; Denon DP-62L w/Ortofon 2M Black
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