It depends on how you use your pad.
I use my spare clothes bag for a pillow, which I want ON the ground at the end of my pad, not on it.
I am 69 inches tall, so, a 66 inch Thermarest Prolite Plus Women's model is perfect for me. The pad starts at my collar bones and my feet still have a little room at the end. I can't stand having my heels on the hard ground - just a personal quirk of mine.
There is no weight difference between the Thermorest Prolite Plus 72 inch men's pad and the women's 66 inch pad; both are 24 ounces. There is a significant difference in the R value of the women's model; 4.6 vs. 3.8 for the men's. I'll take the extra insulation value, which, depending on the season, may allow me to leave my merino wool top and/or bottoms at home. I don't view the one ounce difference in the Neoairs as significant.