The Lina amp and master clock were the same in all the stacks, but in the Bartok listening booth, you could also compare the Bartok/Internal Amp with the Bartok/Lina Amp/Lina Master Clock. In all the booths, I auditioned with my DCA Stealth.Yep, the stacks were the same except the DAC portion and I went through all three with susvara (I'm most familiar with it since I owned one before.)
The jump from Lina to bartok was bigger than going to Rossini imo but there was still an improvement going to Rossini. Just depends how large your wallet is. Lina almost sounded muddy in comparison even though it's not really.
In the Bartok listening booth, at first, I liked the amp in the Lina better than the Bartok, since the low end was more pronounced. However, after A/B'ing both several times, I noticed more detail and separation with the Bartok internal amp. The Lina amp sounded a bit smoother than the Bartok, but keep in mind these are hair splitting differences. The room was quiet and I had to listen over and over again before I could come to any conclusion. I didn't spend enough time A/B'ing the Lina Stack and the Bartok to compare the DAC's. However, after doing lots of A/B'ing with the Bartok/Lina amps, and then switching to the Rossini/Lina Amp, there was a noticeable, albeit subtle, difference between the Bartok and Rossini DACS; for example, on the Rossini, I could hear slight vibrations in the violin or the tapping of the keys on the piano that I couldn't hear with the Bartok.
I gave up on poor recordings at the Lina, since all the dCS DACS were so resolving only the best source material took advantage of them. The dCS equipment all reminded me of shooting for perfection in my two channel system, especially when trying to align all the stars with my turntable rig, so source material became more important as I moved up the chain.