S.H. Figuarts vs. S.I.C.

I'm quite familiar with Figuarts, they seem to be the more popular figures I see in images throughout the internets. But I've always wondered about S.I.C. I've never gotten any S.I.C. figures, only Figuarts. Both appear to be made by Bandai, so my questions are:

1) Which is preferred and why? Figuarts or S.I.C. Is one of them lower quality than the other?

2) What's the point of the two separate lines? Are the scales slightly different?

3) Am I missing out on something by having no idea what S.I.C. is? The prices seem all over the place, but the figures available differ just a little bit (seems like you can still get an S.I.C. Skull, but harder to find that same character in a Figuart).

Thanks for any insight you wonderful people can provide!