Difference in sound using different carts when digitizing vinyl record?

Dear Solypsa, I'm with you.

To the OP: As you apparently realized mid way through the barrage of responses, your question is not about whether digital recordings of one cartridge vs another would reveal differences between them.  Your question is really specific to the Sugarcube and any other component that does what it does. (I am not aware of any other.)  As I now understand it, your question is whether inserting the Sugarcube  in between your phono and linestages would obscure the differences between two different phono cartridges.  Since no audio device is perfect, and since even very modern state of the art D2A and A2D is only near to perfect, I would guess that the Sugarcube MUST not be perfect.  It must alter the signal in some small ways.  Whether you can hear the difference, only you and other owners of the Sugarcube can say.

Incidentally, I own about 2500 LPs.  Nearly half of them were purchased "used", but I have very stringent criteria for purchasing used LPs when it comes to the condition of the playing surface.  I also clean my newly purchased used LPs on a VPI HW17 RCM. (I have not advanced to Ultrasonic yet.)  I just clean them once, after purchase, and maybe never again. Having taken those precautions, it is very rare for me to hear a tick or a pop during playback.  Some older LPs do have a faint "white noise" background, but that is either tape hiss from the original process or surface noise from prior use or imbedded dirt that just won't go away.  I can tune that out.  So, I'm wondering how bad could be your LPs that you feel you need the Sugarcube?  I am guessing that their customers would be mostly younger newbies to vinyl who were nurtured on digital and have therefore become highly sensitized to the occasional (or rare) tick or pop. That's no slur on you;  I only wish I were still young enough to fall into that category.

Michael Fremer is betting that the answer to your question is "yes".  He's been doing this for the past few years and posting the tracks on his website.  Most who have auditioned the tracks seem to hear differences among and between cartridges.  At least they are not afraid to vote for one cartridge over another.  Like sleepwalker says, if I were doing this for myself, I would want to use the highest resolution digital equipment possible.  Else it's possible that one would hear differences but the differences would be misleading, because of the inferiority of the digital phase of the process.