The following might seem to be have a air of Negative as reply.
Note I have had a Tube Pre Amp > Power Amp in use since the 90's.
Tube Amp's command a slight alteration to the disciplines of use that can be used with a SS Amp'.
There is a concern for a occurrence where a fire could be the result.
A Drastic Statement it is, but anybody with a Long-Term experience around individuals with a Tube History, will pick up on the need to heed the above and express a 'Vigilance' when using a circuitry that has Tubes.
In a nutshell, when using Tubes it is best to know any early warnings something is amiss with a Tubes Function, it is most reassuring to be able to see the Tube as a operating component with the Power On.
'Vigilance' means being present and observant, aware of developments that suggests a Speedy Power Off Interception is for the best.
I have disciplined myself to be in full time attendance in the Listening Room , with only very short periods of absences during periods that the Tubes are Powered On.
If an individual like to have extended periods without a observation of the equipment in use, the use of Tubes might not be ideal for such practices.
All who I know with Tube Devices are very similar disciplined to myself, which has resulted in not personally knowing anybody who has had a fire in their set up system. I even know one individual who seen an Element start to glow more red than orange and did not suffer any serious outcome as a result of the immediate Power Off that was actioned.
The same is not said for those I know that extend their use of Tubes to the place where they work with Tube Devices on the Workbench, I know of smoking circuits occurring.
I do not ever see myself without a Tube Device in use, but recent years have certainly introduced myself to SS Amplification that in my assessment could be used in place of my Tube Equipment. I have already pretty much decided a retirement system to be created, may have a Second Power Amp and a few devices that are SS, as I don't have to be so attentive to these when in use.