I've heard the new top of the line MSB and thought it was very good. I would have needed to spend more time with it to tell more, but it has promise. Just very expensive. I have heard the newest Rossini two weeks ago (is the brand new one out? If so, this was it. I didn't ask if it was the brand new one as I was auditioning the new Boulder amp so didn't care). It was very good, but like most of the DCS digital, it's a bit sterile for my ears. Gobs of detail and it is very 'fast'. It always leaves me a tad cold in the mids as do many digital products.
At this level you are talking about shade differences. Folks will have their own flavors they like better. I personally need to get my new DAC/Server burned in, but so far on 24/192 as well as 32/384 all in WAV, it is going to be a contender as a ultra high end DAC. It's a brand new design by Sam Laufer's company. Mine is installed in my Memory Player. It uses two signal tubes and dual AK boards for proper balanced design. Very little filtering. I'm going to learn more about it technically, but don't care as I want it to burn in before I make a real evaluation. We are also waiting on the Stealth bypass caps for it so the sound will change again and hopefully for the better.
I'll keep you all posted, but I was concerned about the DAC in the MP, but this brand new design is just sick and it's the first one they've made so far.