Just finished building a B16. I had one that was assembled by someone else and wanted to create a linked pair so I took the plunge. I absolutely love the sound of these on my drum bus. They both have the steel transformer option and I took the liberty of adding a on/off switch on one of the subpanels for easy link/unlinking. The sound is stunningly good to my ear.
Even with no compression, the tracks sounded more authoritative, a certain weight was added that pulled the drum sound together. I'm guessing that the transformers are a big part of this, as I haven't heard the B16s with out them.
Anyway, two big thumbs up SCA! I have every intention of building two more to complete my CH02 4XA12, 2XB16 so far...