So all I can say is just like all cameras, test it, test it, test it, in as close to the most severe shooting conditions you'll work under and then you'll know what works for you.
I wouldn't consider Abel's "Range" profile to be super flat, but that may have to do with my tendance to light contrasty.
What I do like is it looks much more like film then any of the multitude of bubblegum profiles I tested. Lowering contrast, sharpening, & chroma, plus the use of a relatively neutral cine gamma, & matrix, leads to a softer look with minimized chroma clipping, & a more pleasing highlight roll off. In film terms think Porta NC, vs VC, or worse, Velvia.
But I've never used them with a FS100, only the AF100.
I'd love to burn in the look every time, especially as I'm often not available for the grade, but editorial would not be happy. Even switching profiles for each scenario would be difficult as I almost exclusively work multicam, & it's already too hard to keep all the cameras matched up.
But it goes further than that. When I shot film I chose just a few stocks. B&W was always Tri-X, color was NC. I knew these films, & how to light for them. I feel the same about profiles. Know them inside, & out, then forget about them, & move on to the tough stuff.