I have a 432 and really like it. I have not compared it to the new 5xx models. It seems like the No 532 is an update to the 432 (although at a much higher price) and the 532H is a new, different model. Just from a weight perspective the 432 and No 532 are comparable (120 lb), but the 532H is 40 lbs lighter. Obviously, weight is not necessarily correlated to the sound, but the 532H does seem to be a new line. The 532H is 300 watts/channel versus 400 for ther 432 and No 532. The 532H also does not "double down" when going from 8 to 4 ohm, whearas the 432 and No 532 do. The 532H really looks like a new design for home theater use. I would not be surprised to find that the 432 sounds at least as good if not better than the 532H. The No 532 is twice the price, so should sound better than the 532H and probably the 432. Again, I have not heard these new amps so am just speculating. Maybe someone who has followed the line more closely lately will have more information