Thanks for your input. Yes, many of us are waiting anxiously for the release of the Spectral 4000s. I am also waiting for my SHHA2 module upgrade for my 30 SL preamp.
Have a similar set up as yours consisting of 30SL preamp, DMA 150 Series 2, SDR 2000 transport and 3000 DAC via Spectral link and MIT cables, MIT Z center and MIT stabiliser. Only missing piece is a speaker by Avalon. Currently using Von Schweikert Vr4Jr with extremely good results. Just a question, have you tried the newer offerings from Avalon like Opus and Eidolon? Wondering how it will fare compared to your Radian HC..