Again, none if those are tube preamps. They are solid state preamps with a distortion effect, using a tube starved of enough voltage to work properly, that you can dial in.
Yes, different tube designs (not all 12ax7's are the same design) will react differently to being under powered, so the rrsult can be different when you swap tubes. Also, worn out tubes sound different that fresh ones.
The point that is trying to be made here is that in a real tube preamp, the tube is used to amplify the signal. In all the preamps you have mentioned, solid state amplifies the signal and the tube is used for some effect and marketing hype. There is nothing to say that the tube us even doi g the bulk of the effect. You could be dialing in filter that pushes the mids foward, or dialing out a filter that will make the solid state only setting a little harsh.
(unrelated, but along the same lines, BBE was found to have a filter in bypass mode that made the audio sound extra dull. more dull than if you didnt have the unit in the loop. This of course made everything magically "sound better" when it was taken out of bypass. So there is precidence for companies making certain modes sound bad on purpose in order to give the impression that the feature they are hyping sound like it is doing more than it is.