Vinnie Rossi LIO Or Pass Labs 250.5 & XP10

Congrats. Nice system. I'm not sure how much of an improvement you'll hear, you're already using an excellent amp/pre amp.  Pass amps are quality.  Is the LIO a class A amp? If I recall correctly, I think Vinnie has a pretty good return policy so if you buy it and you don't like it, you can return it.  Unfortunately, I never heard one in real life so can't really comment. Btw, maybe another consideration is to move up to 40.2 or upgrade your DAC. Both would make an impact to your sound. 

What did you decide bg1968? I've read what you experienced - LIO + Harbeth = Amazing. 

I'm about to pull the trigger on the LIO with DHT and DAC2.0 to drive my KEF LS50's. It's my office system and should be a tremendous improvement over my current Rega Brio with Parasound Zdac. Long term, I'd like to pick up the 30.1's.

I am also running LIO with DHT with KEF LS50s.   It sounds great.  You are going to be very happy!  And I also have a long term interest in the Harbeth M 30.1.  I just have a hard time moving the KEFs out - they work so well with LIO.  If you make the move, Keoliphant, I would love to know what you think!  Margot