The 2200II and A21 have similiar specs: - 250x2 into 8 ohms, 400x2 into 4 ohms - dual 1.2kVA power transformers - 12 output devices per channel - same chassis size and weight Anyone know the differences between the two? The A21 (and other Halo and classic parasound amps) have Mosfet driver stages. Does the 2200II? How much does this affect sound? And finally, what relations do either amp have with the JC1?