You pose an interesting question. Of all I've downloaded only one stands out to me Miles Davis-Tutu from HD Soundtracks USA in 24/96. It definitely is a big improvement over the CD and vinyl both of which I own plus I heard this live when Miles did his world tour to promote this album. One of the best concerts ever for me.
Unfortunately there is so little music that I like in hi-res which has always been a problem with so called audiophile recordings. Friends that have these tend to use them to demo or show off there systems, feel the bass, imaging etc. They are not particularly interested in the music only as a tool.
I agree that some of the older recordings in red book are excellent played back but I also love the music warts and all.
I'm very disappointed for example Pink Floyd recently remastered all there albums at 24/192 but publicly these were released on 16/44 CD's or if you bought the boxed set you got a blu ray with 24/96 on it which Chris Connaker(Computer Audiophile) recently ripped to hard drive. Why are these not available for downloads at a price I'd be happy to pay. The 24/192 must sound amazing.
Bjork's latest album Biophilia download is available from her site in WAVE wow! but only 16/44. Why not offer 24/96?
Part of the problem is record companies still have not got there head around this whole download situation and we as audiophiles are still a very small part of the market less than 1%. Lets face it MP3's have replaced CD's and the urgency to provide high res is minimal.
Recording studios are another whole issue. This is a small piece from Barry Ober The Sound Doctor JL Audio who has extensive experience with studios:
THE RECORDING PROCESS
On top of all the previous variables we have all the issues and errors inherent in the recording process. It is simply laughable (and pathetic) when I read the magazine articles where the "soundstage" of a rock recording is "palpable". Sorry, but every modern rock recording made in the last 40 years is composed of a series of panned mono signals that have absolutely no "depth". They are each separately sent to an echo/reverb device, the returns of which are usually (but not always) panned full left and right. The summation of all the L-R panning placement and the summation of all the reverb returns fools you into thinking there is a "soundstage". Sadly, precious few recordings are made with any regard to true stereo or binaural sound in anything resembling a true form; even better classical recordings of large orchestras have morphed into combinations of stereo miking and "some" local more-nearfield mono miking added to the mix to achieve whatever the producer determines is a suitable balance, perhaps between a soloist and the rest of the orchestra. Yes, there are precious few companies who do pay attention to this; AIX records is one. But to think that any modern, commercial pop recording mix has any true acoustic space is, for the most part, sadly mistaken.
This is a piece from connecting subwoofers to systems
http://www.soundoctor.com/whitepapers/subs.htm but this bit on recording I find depressing reading.
Its still early days though and hopefully more high res stuff will become available. I personally think the artists need to take over and offer them directly. Potentially 24/96/192 is amazing and a big step up from 16/44.