My mistake Dick.  I just assumed that a VAPOR was another of the flat foamie 3D models.  I've since looked it up and see that it's a spider web like model with some superlight gear.

Seems to me that what you're looking at as a bigger version already exists.  I don't remember the name but there's a model that's been around a while with the same bent carbon rod and film flying surfaces and that uses a small carbon tube for the fuselage.  It has around a 30 inch span as I recall and a V tail.  Although it used regular RC gear instead of the specialized small stuff of the VAPOR.  Sorry, no idea of what it weighed.  But it did slow down really well so it couldn't have been much more, if any, over 4'ish oz.

Same idea of the oval bent and curved up hoop for the wing that when covered and shrunk automatically gives a cambered arc airfoil to the covering.

The key to keeping the weight of a bigger version down will be finding the optimum small gear, motor and battery pack.  But if you're talking about a double size one then you can let the wing loading creep up a little and still fly the bigger one at the same speed.  And with the wing area going up by a factor of 4 times this means you can aim at a 3.7'ish oz weight for a 30'ish inch span.  That should be doable with care.