I think it defintely depends on the baby and the mom and history. My first son was born at 37w6d after my water broke the day before (stupid hospital birth, induced because I didn't know I could wait for contractions to start on their own, epidural). He was 6lb15oz and 19" and had no problems breathing, he did wait to nurse for 14 long hours-side effect of the epidural. My daughter, baby #2 was born at 39w3d UC. She was 6lb12oz and 19" and had no problems eating or breathing. My second son, baby #3 was born UC at 35w6d. He was 6lb5oz and 19". He had no problems breathing or eating, but he had a tough time maintaining his temps for a few days, so I wore him skin-to-skin+diaper in my shirt for a few days. No big deal. He was also pretty yellow, but I think a part of that was his double black eyes thanks to being born posterior. Monster. We sat in front of the sliding glass door a TON with him, and he was fine. I felt all through the pregnancy that we would be born in an undesirable position...I first thought breech until about 18w when he very obviously picked head down and posterior. He didn't change. At our u/s, I found out that my placenta draped to the front. I know I make pretty short cords-just long enough for the baby to be born and for me to hunch as far as I can and nurse before cutting the cord. Anyway, having this feeling from the very beginning that he'd be born in a strange position, I prayed that he would be born early enough to fit with no problems, but not so early that he had problems. The night I went into labor, I had my hand on my belly and I felt what I could only describe as the feeling of his little abdomen expanding-practicing breathing. I took that as a sign from God that he was indeed ready for life out of the womb and labor started within an hour or so. He was born 4 days later.
So yeah, my answer is that it definitely depends on the baby and the mom. If I had a history of giving birth at 42w, I probably wouldn't have been ok with almost 36w...but then again, I just had this peace from God, so I don't know. It's all about God to me.