I used Elmers on my Gemini, and it worked well.
Note: if you want to paint it to match the packaging, you'll need to paint your fins before you attach them. Why? Because Estes only gives you 4 decals to cover 4 fins (8 fin faces). So you can either make your own using a scanner, a color printer and clear label paper, or you can just paint them using the old mask-and paint technique.
My 2 cents.
(if I keep giving out 2 cents here and there, I'm gonna be in the poorhouse soon!)
WW