Amp for Nautilus 805 - Krell KAV or Classe cap 101

I want to change the amplifier for my Nautilus 805.
I am currently using musical fidelity a3.2.
When playing symphonies, mf seems to lack in power.
I have placed the speakers in the living room, so I would say that it is a medium sized room.

I am thinking of changing to krell kav300i, or classe cap 101.
I think krell would have enough power to drive 805, but a little bit worried that it might sound harsh.
Cap 101 might not have enough power to drive 805.

Thanks for your comments!