I think it is easy to be die-hard when you aren't actually in the situation. It would be really easy for me to sit here on my computer and say "well, there is no reason for x,y, and z and she should just do this..." But, I believe it is more important for a woman to trust her own intuition and feelings. I believe the primary goal of UC (or any birth) is to have a healthy mom and baby, most UCer's believe that they are making the choice that is healthiest for their family. If they start feeling intuitively that it isn't healthy anymore and they need to transfer, who the heck am I to say differently? I recently had to make the same call in my birth. I had to turn my birth choices upside down because of what my intuition was telling me and while I mourn the loss of what I hoped my birth would be, I am very happy that I am fully healthy and we have a beautifully healthy little girl.
Things also become less cut and dry when you are no longer on your first child. If I felt my life was at risk, should I just let myself die and leave my other children without a mother? All for what? Because I was against going to the hospital and getting some medicine that could have saved me? Freebirth2, you seem to have all the answers, but life is just not that black and white, there are lots of shades of grey. I guess you have to make whatever choices you feel are best for your health.
As for the original question, for me it isn't a matter of hours in labor... it would be a matter of lots of other things. If I felt I needed to go in for anyreason, then I would. If things were going along nicely then I would stay home. My homebirth was 24 hours of labor, but I felt at all times that we were healthy and there was no reason to transfer.
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