[Arran]

This is a curious attitude as many guitar tube amps originally left the factory with solid state rectifier diodes. I was looking up some schematics for Orange brand amps, and that was what most had, along with the power output tubes in push-pull-parallel, the Fender ones were more conventional with tube rectifiers. In the end it doesn't really matter, a directly heated rectifier tube is almost instant on in terms of conducting, the main difference is in the forward voltage drop.
Regards
Arran