I use a Raven Concealment Vanguard often. It would not be the holster I would choose for class because of the need to reholster repeatedly. In class, I would use the Fricke Archangel for exactly this reason.
However, in twenty years of concealed EDC, I have never once had to reholster my weapon outside of my closet, never mind do so one handed. If I make the decision to reholster, it will be because I have become convinced that there is no longer a threat, and I will reholster reluctantly.
I'm not going to make decisions about how I EDC based upon the most unlikely scenarios, including one handed reholstering. That's just not a factor for me. I'm going to make these decisions to maximize my utility for the purpose to which the gun would be put. For that reason, I want a safe carry method that is comfortable, provides good concealment and retention, and allows fast access with either hand. The Vanguard accomplishes this, for me.