I've not heard it but linear supplies generally don't have some of the noise associated with SMPS. If Sutherland deem it an improvement, it most likely will sound a fair bit better.
How important is a Linear Power Supply Versus a Switcyed one?
I recently purchased a used Sutherland Insight phono stage to replace the built in one in my Plinius8200 MK II integrates amp. I was amazed at the improvement in openness and presence. It comes with a switched power supply but there is an option for a Linear Supply for about 35% of what I paid for the Insight ($350). I have a Van den Hul One Special cartridge (if that matters). Is it worth it?