I know Bryston is very accommodating when you call or send an email, but wouldn't it be better if there were charts posted on Bryston's site that let you look up a serial number and see where that unit stood on product improvements?
I envision a simple chart with the key being product, then product change and serial number; pretty much a two column excel spreadsheet. I would expect that data to be readily available from Bryston's production quality control systems.
So if we are looking on the used market; we could, by serial number, know what the build was for a unit.
Is there a reason Bryston would rather we call?