Plinius 8200 vs. 9100 -Which one?

I'm looking to buy a warm SS integrated amp and have wanted the Plinius for some time now, but never took the plunge. I'm looking at the lower end of their products or older discontinued.

Which is the better sounding amp of these two? The older higher powered 8200 or the newer lowered powered 9100 integrated? (I have 4 ohm, 87db speakers in a 18'-22' room in a lively minimalist room w/ hardwood floors.)

Furthermore, does someone know what is the difference between the 8200 mki vs. mkii, and is there a sonic difference?

Thanks fellow A'goners