GiantScalePlanes.com/CreekHobbies Extra 330 Wing?
Yup, this has been discussed. Do a search on Creek Hobbies Extra and you'll find information about this.
Suffice it to say that the spring is NOT enough. Most of us who have one, have gone to alternate methods. I use zip ties in addition to the spring. I'll have to check out that aluminum cross brace. I haven't heard of that yet.
Mike