Vintage Krell Amplifiers from the 80’s & 90’s.

Hello all! What do you think of the Krell KSA-100, the mighty Krell KRS-100 or the Krell-200 Reference Series Monoblock Amplifiers? I think it is better than the Krell KAV. The KAV is good I just think the KRS is better sounding in the middle and highs. Both have great bass slam. I have also owned the mighty FPB-700 and the Evolution 402e as well as the EVO One. Some say the Evolution 600 and 900e was better than the Evolution one. I can't comment since I haven't own them. Hard to beat a high current Pure Class A Monoblock Amplifier. What are your thoughts? Also the Chord SPM-6000 was incredible as well. Please chime in.