Belles 350A Reference vs. Pass INT-150


Hello, I am currently running an Opus 21 cd player pre-out
to Belles 350A Reference to Dynaudio Special 25s. I'm wondering if the Pass INT-150 has significantly: lower noise floor and finer midrange to high frequency detail, plus better imaging than the Belles, or would this be a lateral move? Would appreciate any comments from someone who has compared INT-150 or X---.5 series with the Belles.

Also needing more inputs, so considering adding a pre-amp to the Belles instead of switching to an integrated. I liked the natural detail in the (discontinued) Herron solid state pre-amp, may consider one of the more recent Herron tube pre amps.
jmlm
Only familiar with the Belles 150A and the XA 30.5 Pass gear, but between these the move is definetly not lateral. Do you have a Pass dealer near you? This might really require an audition for you to decide - the X series is certainly a bit different sounding thatn the XA.5s
Thanks for the responses! I think that my Dynaudios would benefit from more power than the 30 watt XA 30.5, even if the sound is more liquid and refined. If I get to hear the INT-150, I'll post my impressions.
I don't think you can wrong with most anything by Nelson Pass. Good luck if you go that route!
Anyone have experience with Belles Reference 350A and Pass X-150.5, NOT XA series? XA is more expensive than both of these similarly priced competitors and considerably lower power.