You might want to also consider the Parasound JC-1 amplifiers. They’re ideal for driving these electrostatic speakers, for their power curve is the opposite of the speakers impedance curve. I drive five 945’s with five JC-1’s above actual symphonic hall listening levels.
The impedance curve of the SoundLabs range between about 3 Ohms at 20KHz, up to about 30 Ohms at 20 Hz. But acoustic music requires almost all its amplifier power below 200 Hz, and very little above 10KHz. So with the JC-1’s +/- 100V DC power supplies, the amplifier never gets out of class A operation, but delivers very satisfying listening levels of classical acoustic music.