aestetix rhea - the groove - sutherland fono stage

I recently heard "the groove" in my system and I was very very impressed about sound quality. Now I am thinking to buy it.... Who can tell me if the groove is better then the rhea, or the battery powered sutherland? and... is the io signature a completely other legue?
My system is Emt 930 with emt tsd 15, pre fm acoustics, convergent jl2, eidolon diamond.
Thank you very much...