He does not mention what version of cubase is used on the CD test (circa 2003). If it was Cubase SX, the audio engine is the same as nuendo, but Cubase 32 and 5 were an older engine and sound like mud compared to Cubase SX.
To answer you question, yes they do sound different but not better or worse. I have used Cubase from back on 3 through Cubase SX. Tried Sonar for a while and didn't like the layout or the CPU hit. Switched to a mac a ran DP4 for a while, then bought Protool 6.4.1 and a mix plus system. Still have it but I am now running Logic 7 as well.
I Like logic the most. I always felt that playing files back in PT sounded diferent than the bounce playing back in itunes. I think that my mixes sound the same after bouncing from logic. I trust that what I hear is being translated to disk identically.
I would not run Cubase on a mac. If that is your plan do some searching on the net. I have heard some stories about issues. On a PC it would be my go to production app. Very solid and so many free and cheap plugs like the voxengo stuff. Cubase and Nuendo are going to sound better than PT if you record through a an interface that is superior to the digi hardware IE: Digi002.
Protools LE is also a CPU pig compared to Cubase SX. Afterall Digi wants to eat up all your CPU so you think you need to buy expensive HD systems. You will get higher track counts and a better mixer in Cubase SX, and the VST plugs are so cheap and some of the best sounding plugs you cna buy on a PC.