There are many user comments about the short NeoAir pads being somewhat too thick and there is a "drop-off" to the leg area which can be a deal-breaker for some people.
Also, there are comments about the user being "pitched off" the pad during tossing and turning.
So, I'd recommend a demo of a friend's short NeoAir, or something like that.
Some people have bought the short, liking the light weight, but could not overcome the drop-off at the legs, and ended up getting the regular pad afterwards.
No doubt it is very light, and that's great, as long as you can sleep well on it.