Keithr: The darTZeel integrated is stable into 2 Ohm loads and outputs 450 watts into this impedance. The power supplies on it are very stiff, which should come as no surprise given its considerable cost (I think the integrated is now something like $25,000). The issue isn't whether the darTZeel will drive a speaker like the Sasha, which it will, easily, but whether a speaker like the Sasha, which is well-made and does some things very well, but is not state-of-the-art, should be paired with extreme cutting-edge electronics like darTZeel (there are a lot of people running Wilsons with darTZeel who are extremely happy, but they don't know what their integrated is fully capable of).