I found two threads on this subject:Voyager vs. 2 Slim PhattysMoog Slim/little Phatty vs Voyager RME
The latter includes my own basses demo from 2008. I was experimenting with the dual filters in a feedback configuration while boosting the oscillator mix's treble with a sonic maximizer pedal to get most of those sounds.
The gist I get from what I've seen over the years is that they both exhibit character one associates with the Moog name, and the Voyager appears to have more sonic potential, but more people seem to appreciate the phatty's more, both in terms of character and ease of use: a better price/performance ratio. I always point out the Voyager tends to sound less bright and cleaner/smoother, while also having a deeper low-end. Its stability combined with use of the Highpass filter or high resonance make it sound downright digital at times. Being able to program it to the extent of doing things like modulating resonance and cutoff together for filter sweeps, in order to get more low-end, is nice. The external expansion capability is nothing to sneeze at, but you can do alot with just the internal mod matrix.
I sold it some time ago while unemployed and mostly now I just miss the envelope and portamento behavior! What the charlatans tend to call "musical", whatever that means. Very useful for leads anyway. Too bad the Model D excelled at leads in some small part due to how it could cut through a mix. Trying to do the same with the Voyager is a hopeless task.