Well, you need that ammount of latitutude (well, it's ideal, anyway... if you have $800 for a 1000' roll) because even very will lit scenes can have a very wide range from the brightest highlights to the darkest shadows, and basically, you WANT to capture detail in ALL the ranges, because you're going to be scanning the final cut at 4k when you do the online edit (color, effects, etc.) It's mostly for the color grade, and the characteristic curve extends WAY further into the shadow reigon than any still film does (about 4-5 stops!). Kodak says in text that it goes 14 stops, but the actual curve that they provide, I only count about 10... I dunno, most people say it's 14.
Anyway, about still film latitude, thanks for the reply. I hope I get a variety of answers, but yeah, due to the cessation of many awesome stocks, it's not surprising that we some of the answers have changed. I think you're right about Portra NC... shame they had to make the new "hybrid" bullshit-- I wanted the option!! We all did! I guess for now, I love Ektar, but I'll have to do shoot some charts if I can get my hands on some NC 400/100 to compare it with.
Thanks for your input!