Bruno, this morning I had a chance to play my Pro-36 and Piano-36 in combination with the 44 and the Hyper and if I had to choose a (3) melodica combination, in my opinion and personal choice I would probably choose the Hyper. To me the three are sounds I like and would probably use more. The Piano-36 does sound closer to the Hammond 44 so why have sell the Piano-36 for now. For me sound wise I prefer the Hammond 44 over the Piano-36 so that would be my future melodion.
Hope this helps