If it sounds better to you, that’s what counts.
But I would say that if you had been listening to that previous set of tubes for quite some time (as it sounds as if you have been) you hve been hearing, and are experienced with, the sound of them gradually degrading after they were at their peak.
I am thinking it is possible that what you are hearing now (that sounds so good) is the sound of tubes that have not degraded from their peak. For the comparison to be fair and accurate, I would think you would have to have the original sound of those original tubes, when they were new, fresh in your ears/mind.