My brothers have both used this for props in the last few years and while they got some bubbles, they didn't get huge ones because they sprayed it in small sections and even used the spray that specifically said for gaps 1" or larger. Both of the props were quite large, one being Alice's Hobby Horse from Alice Madness Returns
and the other was a 1/1 scale Kakuna from Pokemon
. For the Hobby Horse, my brother first made a skeleton of cardboard, so he had these little shelves to fill in instead of spraying a blob and then carving. I don't know if Kakuna was done that way, but I think it was.
If you want, I could always ask them about what they did in more detail and share it with you. I know my brother at one time was going to make a tutorial on how he did the Hobby Horse, but he's never actually made it.