Try to listen the Accuphase E-530 in your room.I've tested the MF NUVISTA and E-407 in my system, and i preferred the Accuphase sound(and build quality, of course). When i tried to listen the E-530, i realised that this is much better than Nuvista and E-407. They sounded lean, weak, without impact and musicality next to this class A design. Its power is 30 watts/8ohms according to the manufacturer, but the reviews of most European magazines speak about 47w/8ohms, 92w/4ohms, 184w/2ohms and high stability at 1ohm.Just avoid to use low efficiency speakers(<87db) into a large room, in case you play loud. Using this amp, i was always concentrated and listened to the musical event. Using the other amps(especially the NuVista), i realised that most of the times i was listening to the amplifiers. This comment says everything, i suppose. The E-530 was more natural and full bodied from the lowest bass to the extreme highs. For my ears, this amp sounds very close to a "small" A-50V(the best ss amp i've ever heard together with the ML 33H) but at a much lower price.The build quality is uncomparable.By the way, from the amps you referred, IMHO the best amp is E-407.