Well i dont 100% know, but others have explained it better than i could ever do on other forums, etc. But its not all about the data, the file data will be the same i believe, its about all the other stuff that goes on when you rip, like noise, etc.
The standard buffalo does a very good job and for its price, its good value. I wouldn't buy a D100, and i didn't, i borrowed one. I simply don't have enough CD'S to warrant its price, but as i have said, i could tell the difference, its not huge, but it is better.
To make things worse for me the D100 takes atleast twice as long to rip a CD, over the buffalo, quite depressing when you are doing them all again, and i certainly wouldn't have spent hours each day, for weeks, re doing them all for nothing.
But as said you are going to have a very revealing system, if not then its simply not going to make any difference, that you are going to hear, bit like most cable and mains debates, but if you have and you try it, then you might find a new rabbit hole to go down, one that will end up with you spending many, many hours ripping all your CD's once again, i certainly hope to never do it again. Back up, even more important if you havent already got it, and probably more important than this rip debate for 95% of hifi people.