ive always used a heat gun on solartex, i mean i dont cook it, just enough to relieve the small wrinkles and make it smooth and taught. never had a problem with it bagging out after, you just have to be careful. sometimes even if your real good with a iron you may get a small wrinkle or crease around a curve and a sealing iron just wont work where as a heat gun will if you use it right that wrinkle just disappears. this is a very interesting subject and would like to see more people chime in on this and let usknow what there tecniques are. i'd like to add that i don't use a heat gun on every surface of a build only when needed.