I am 6'3" and the large fits me well. I am very happy with this pad. It is cheaper than the four season version and is only marginally larger and heavier. I felt it was a good decision to save the money and get the trekker vs. the other pads available from thermarest. Mine has never leaked air through the night and typically stays inflated for two straight nights. It is very tough and durable, I would recommend this to anyone looking for a good nights sleep!