I believe that all speaker manufacturers should supply impedance v -phase graphs with their speakers.
No one yet has done one to give a good indication of if a pair of Krell mono blocks are needed or they can be happily run from a 10w single ended tube amp.
So to suggest an amp without knowing impedance curve vs -phase curve would be purely a subjective opinion 50/50, or a dealers opinion, and we know they that can be questionable sometimes, depending on what they need to shift.
To be safe returntomusic if you must go with your few options, I go with the one with the most watt/current and I think that would be the John Curl Parasound A21
Cheers George