I was originally feeding the SB2 Digital out to a Yamaha RX-V1000 as Pre/Pro (using the Yamaha DAC). Using the Slimserver Preamp Volume control, I can now feed analog directly to my Sunfire Cinema Grand amp (feeding ML Aerius speakers). This latter setup yielded more crystalline highs, and clearer bass, though, like others, I believe the latest version of the software/firmware has taken a step back in sound quality. I am awaiting the next beta software that supposedly will rectify this issue.
So, YES, the new firmware WILL make a difference, but you'll need to judge if it's better or worse <g>.