I looked at one of those a while back and while the design is good there are a couple of factors you'll want to take into account...
1) Wind...you set that thing up and then you have to watch that the wind doesn't blow it away.
2) Theft...if this is a great idea for a photographer no doubt others may want it for themselves and so you are constantly having to look where you set it up to see if it's still there.
My suggestion...a couple of hulahoops and opaque material pinned to make a tube. You set it on the ground, the model steps in, you raise it high enough to afford her complete privacy (ie. make the tube long enough...6 ft.?), the model changes outfits, you lower it to the ground and the model steps out of the hoops. PrestoChangeo. [This is an actual unit I saw another local photog use on the beaches].
There is one thing though to this...hulahoops don't bend well to make it smaller so if you have a compact or subcompact you might have storage problems in your vehicle.
I'm planning on putting together a tube with hoops made of smaller diameter PVC piping and 45 degree joints. I think the breakdown would make this a far more portable unit.
"Beauty is more than skin deep"