Kurt Tank,
JKA's methods are extremely tough as-is. The only thing I do differently is cover them with TowerKote or EconoKote instead of the kit-supplied packing tape. A light coat of 3M77 over the foam parts makes the covering stick very well.

Using Rip-Stop nylon would be fine to use on the wings. But, its really not required and only adds to the cost, weight and time to build it.

Rip-Stop will not work well for fuselages because it does not conform to compund curves very well at all.

This pic is of a prototype JKA P-47 that I'm still flying in combat:

This shot was taken in August of '01 and is posted on the RCCA's Photo Album here:
http://www.rccombat.com/sections/album/album.htm

HTH,
D