I have the Audio Logic 2400, and use a Forsell Mk. IV (just updated) transport. I have been very happy with the sound of this combination. I borrowed my dealer's Purcell (dCs) upsampler to see what it could do. After it warmed up, I couldn't live without it, so I bought one from him. I'm sure it does more than just upsample, but I'm absolutely sold on it. Another step closer to analog in harmonic rightness, dynamics without strain or stridency, particularly in the high frequencies. I have also heard the MSB III with and without upsampling (there's a switch on the back) and found the upsampled output to be preferable, though not as dramatic as the Purcell. It looks like the concept is showing up in a number of processors (such as the Bel Canto). The only negative I've got to report is that, at least to some people (such as my dealer), some discs may sound overly lush with the Purcell in the signal path--they prefer a leaner sound, and it varies from disc to disc. I have no such complaints, but I listen primarily to classical music. Hope this helps.