I have them side by side for one month now. I can't tell any difference between them. I am using Virgos and Khorus.
I think if your speakers are not efficient then you need the 8200 for more power( and phono), otherwise 8100 will do.
BTW, both of them sound wonderful. I had owned Classe CAP150, Creek 5350SE, Krell 300i and Musical Fidelity A300 and M3. Plinius beats them all except M3 has better transparency. 8100 and 8200 are very musical.
I think if your speakers are not efficient then you need the 8200 for more power( and phono), otherwise 8100 will do.
BTW, both of them sound wonderful. I had owned Classe CAP150, Creek 5350SE, Krell 300i and Musical Fidelity A300 and M3. Plinius beats them all except M3 has better transparency. 8100 and 8200 are very musical.