Would switching amps make a big difference?

atmasphere,
Let me elaborate on your statement, "since solid state amps tend to double power as impedance is halved, right away you can see that the MLs will be a bit bright if the amp actually got away with that."  Actually, I think that although the SS amp has the capability of providing 2x the power as impedance is halved, the SS amp is still flat in freq response at any given moderate power demand for higher impedance.  For example, a 200 watt amp capability at 8 ohms will still output the same power across all freq below 200 watts.  I would be wrong if this SS amp only puts out 100 watts at 16 ohms, 50 watts at 32 ohms, etc.  What do SS amps usually put out at these much higher impedances?  If my numbers are correct, then for an electrostatic whose load varies from 32 ohms in the bass to a fraction of 1 ohm in the HF, the sound below 50 watts of output would be uniform across all freq, not bright.  

atmasphere,
The essence of my post is that although the SS amp has more power capability into low vs high impedances, that doesn't mean the SS amp will have a tonal balance skewed toward the HF when driving an electrostatic speaker.  To use our numbers, consider an amp with max capability of 200 watts into 8 ohms, 50 watts into 32 ohms, 800-1600 watts into 1 ohm.  Let this amp drive an electrostatic speaker whose impedance is 1 ohm at 20,000 Hz, 8 ohms at 2500 Hz, 32 ohms at 625 Hz.  This assumes impedance exactly inversely proportional to freq, although I have ignored capacitive reactance, the true parameter.  At 30 watts of output, the amp will put out that same 30 watts into any freq for an even tonal balance.  For 200 watts of output, only freq above about  2500 Hz will be undistorted into that speaker, whereas at freq below 2500 Hz the amp cannot put out as much undistorted power, so I agree that under these conditions the amp will sound bright driving the electrostatic speaker.