I prefer full cuff, because they stay on even if you’re not holding them. One poster said he was afraid of getting full cuff crutches, because when he fell down he would get tangled up in them. My response was that if he was falling down regularly while using crutches, he shouldn’t be using them.
I am now eating my words — I fell twice this weekend, got tangled in the crutches both times, and am very bruised and achey today. I especially did a job on my wrist, which makes using the crutches that much more interesting.