I was on the fence for a while regarding the One C from both, but I've finally decided that I like Devacurl One C better. Like MH said, it does have better slip. DevaCare is thicker and I do like it, perhaps it is slightly more moisturizing, or that could just be the thickness tricking me, but I do think the regular one gives me better slip and detangling. One C is the only one from the Care line that I've tried, I use the rest from the regular Devacurl line, although I was curious about trying the D-Care No-Poo.
3a/2c f/mii. pics added 2/3/07