I play on a worship team and we usually have a song every month or so that needs a basic analog bass synth (think Moog Phatty). I had previously been using a Roland GR-55, which I got to avoid having to learn synths and keyboards. I was only using a synth bass patch so I got a C4 to downsize what I had to carry around (I can now fit everything I need in my bass case). I was quickly overwhelmed with all the options and was not able to find a preset from the community that sounded right to me. I tried a few but was unable to get anything usable by blindly fiddling with options. I also found I could not edit existing patches using mobile app, it could only create new ones and burn them. This could have been user error on my part, but it made it impossible to make modifications at the gig.
So over my last vacation, I read a book on subtractive synths. That opened the pedal up to me. I was able to quickly put together an excellent patch that was close to an analog bass synth and the sound guys loved it.
After reading that book, I did end up buying a Novation Bass Station so I could make more adjustments on the fly, but I'm not going to get rid of the C4 because of all the other options I can use with my bass.
So in my experience, this may not be the pedal for you if you're just looking for a synth pedal with some pre-built synth patches. But if you understand synths, this is an amazing pedal.
I would be curious if the mobile app can actually edit existing patches. That would be an extremely useful tool to adjust a patch live (beyond what can be assigned to the option dials).