[grs]

I'll just add my 2cents here.
I recently ponderd better sound in the last year, so I did some tests to see what kind of upgrade I would actually see results from.
I tested a few things on a production and here's what I found.
Upsampling a 44.1 mix to 88 or 96 to master it and then resample to 44.1 gave negligable benifits.
Recording my virus parts and rendering vsti synths at 96 or 88 and adding them to upsampled wavs to make a new mixdown did some improvement, mainly in the vsti synths.
Mixing all virus parts (3 stereo busses) in real time with 4 stereo busses of my production in the analog rhelm. MADE A HUGE DIFFERENCE, like a cardboard wrapping was torn away to reveal the silky inner of space and depth.
At the time I had no analog mixer and made a passive summing buss network fed into a stereo preamp. I recently improved the setup using a Manley solid state pre, that sounds crystal clear.
The ironic thing is I made such a difference mixing out side the box and I'm still producing at 44.1.