A dim recollection - Changed an Alps Blue Velvet for a Black Silk in a Densen BEAT B100, my own personal unit because it had clearly failed and the channels balance was way off until about 40% in.
The next owner (someone who was here at the time - I've been kicking myself for 10-15 years for moving it on) blew up one channel and it got sent back to Densen for repair. Which they did, I believe, for free. But they asked the new owner if it had been modded and he said the voume pot had been replaced. Apparently they told him that the change to the Black Silk (think it's silk - I bought it from RS and they don't seem to have them now) was the only upgrade they believed worthwhile to do to it.