Well, I tried the EDI Solid-Tube R-3DS3 for a few moments, and it did not catch on fire, ran it for 5 min, it did not even get warm.
will try to run it longer.
Which is odd now, that the SK3756/508 version fried in 90 sec in my other set.
tube seen here.
(
https://www.ebay.com/itm/284317947319)