I don’t have any footage saved that I’m able to share since the projects haven’t been released yet, but there are a couple good examples of what you can do with the DNG vs baked in 709 (see links below). You don’t need to tweak any settings in the Pixboom Cine software if exporting the DNGs, as you can adjust things in Resolve.
My first samples - #14 by BKA88
Davinci Processing, Send over your tips and tricks
One thing to keep in mind is that the Spark is advertised as having 13 stops of dynamic range. Even if it’s a little less than that, Rec709 typically compresses your dynamic range down to 6 stops or so (the original range was only 5 stops from 0-100% before adding up to 109%), so the baked in 709 is tossing out some dynamic range that you might want when tweaking the image.