Oh, come on, Rupert Neve designed this thing, it has to sound awesome, it just has to!
Well, I don't know if does or not. My favorite passive DI at the moment is the good ol' Radial JDI. After that, it's a toss-up between the Radial J48 and the Countryman Type 85 (Both active, both sound great).
I'm going to spring for an RNDI and see how it sounds. I'm hoping that it may fend off my desires for a REDDI DI, which, I know, is a completely different animal. Hard to say how that's going to come out since the REDDI is known for adding its character to the sound (my church FOH guy, an outstanding pro audio veteran whom I trust implicitly, sez our REDDI is not an "honest" DI, even though we both love what it does) and Neve consoles are known for their transparent character, which makes me believe the RNDI is built on the same principle.
Now, every bit of this may turn out to be a total and complete crock. I'll know before long...