Upgraded to the Babyface Pro after my 4 year old original Babyface died on me in the middle of a mobile recording project. It turns out the problem with the original unit was simply a breakout cable and was easily fixed, however I'm very happy with the upgrade! Metering is improved with simultaneous input and output meters, 2 extra 1/4" input channels, an extra 1/8" headphone out (which can run simultaneously with the 1/4" phones out), headphone output seems higher, and as a bonus all of these connections are mounted directly on the unit rather than via clunky breakout cable. The one exception to this is the MIDI in/out which connects via separate breakout, however all of my MIDI runs via USB nowadays anyway.
I am able to run two phantom powered condenser mics via USB power alone. The old babyface sometimes had problems when running only on USB power, for instance sample rates over 44kHz wouldn't work. No issues with that on the new unit so far. Sound quality is still excellent and the build quality feels better than the previous version. The main rotary encoder is smooth and solid and the whole thing has enough weight to not slip around on the desk.
One feature I would have loved to see is separate RCA S/PDIF ins rather than combining it with the ADAT optical. Overall an incredibly well-designed and road-worthy unit for small gigs!