3v sounds reasonable. But I believe there is still charge remaining at that point, perhaps not much. When cycling them to check capacity I would go all the way to 2.5v per cell.
I would imagine that a fully charged 3S will probably read 10.0v or 10.1v and stay there for awhile, maybe quite awhile. So if you see 9.9v on your display you may ought to land. Lol.
Let me know how it all works for you as I am very interested as well.