GrannyR,
Except for L7, the Lamp Dacs run the tubes at only 20-25% of rated capacity, so they should last 10+ years. Tube aging is NOT an issue. Indeed at about 20w output, you can leave them on indefinitely without a big energy bill and they will always be "ready". I often do that, except when away on a trip or something, so really no different from SS. In my L4, I have found great Tungrsam NOS tubes for as little as $10 locally and $25 on Ebay with shipping included.
Lukasz told me he made arrangements in case of his untimely demise to immediately release all his schematics publicly online, as he would never leave his loyal customers in a lurch.
In terms of the global economy, small boutique places will likely survive BETTER than larger entities with BIG fixed overheads, etc.
Interms of Transport, that is a different discussuion. DallasJustice had the Empirical Dac with all the trimmings and abandoned it for a TotalDac with Legato 16/44 transport and I think moved on to TotalDac Server and USB converter. I have heard the TotalDac and its very good, but didnt induce me to want to change from lamp.
Many claim the Lampi SB Transport is the best they have for RBCD, especially when fed by Ethernet. I cant say as I never had this experience. I can saw that Lampi DSD is sublime and if any solution is not doing DSD well, I am not interested.