I've got the Bolder Cable digital mod. Again, definitely a step up from the stock unit. Quieter, smoother, etc.
Did you upgrade the PS at the same time you had the digital mod done? The reason I ask, is that I wonder if the improvements you hear result more from the internal mods rather than from the upgraded PS. Hopefully I'll gain some improvement by just upgrading the PS. I'd hate to be without my Duet receiver for very long. How long were you without your receiver when you had Bolder do the mods? I wonder if Cullen Circuits does any mods to Logitech devices??