I know there's more to this unit than the volume control but I feel it must have a huge influence on the sound quality.
How do you feel about them?
All switches impart a sonic signature. It has to do with diode effect. I suspect the reason you're enjoying the Burson has more to do with the circuit design and buffers than the switch.
FWIW - I like stepped attenuators too. I especially like the Seiden switches. However, my Lightspeed attenuator and Truth preamps (both using LDR technology) eliminate the switch from the equation and compared to other passive or buffered devices the difference is noticeable.