Gene,
I've poured two like this. the first had a perimeter of under 100 feet, but 10 corners, including two odd angles. The other was small and simple. In both cases. I had 4 feet of ICF form on top of the footing form.
I also used the "Menzel Method" as described on Fab form's site with a couple of small modifications.
It went perfectly. Absolutely trouble free. The Fab Form alone will save a ton of time. The monopour, which is a rarely used technique on the East Coast of Canada, also saves a heap of money in material, one pump charge ($500 here), and one lot of leftover concrete.
One change I made to Paul Menzel's method was that I used hat channel across the footing form. He used something else. that's of no consequence. The other was that I got the mud delivered quite dry, at a slump of about 2". I filled the footing form first, vibrating it into place, then wetted it up some and poured the ICF. It was clean and easy.
Despite the whole assembly looking like a good wind might take it away, it held the concrete and held it where it was supposed to be. the heights ended up being right on, exactly where they were when the pour began and there was no change in location that I could measure.
Ron