ok- jumping in on this one-
Gotta trust me here. Gorilla Glue is BY FAR the best for foam. I've tried them all- Liquid Nails- on white beaded foam melts it and leaves a groove where the foam touched the glue- and if you use enough, it'll melt all the way through the foam and ruin your prop! Ask me how I know that!!! It's great for gluing wood together- does ok with the pink/blue foam- but it's tough to sand/paint, and once dry, will and does crack and crumble away along the seems.
Just tried the PL300 on my new columns. That stuff SUCKS. Once it's dried, it pulls apart VERY easily, cracks, crumbles, etc. I had to go back and re-glue it all with Gorilla Glue. 1-2 hrs with Gorilla Glue, and it's rock solid. It's not coming apart. I just wish I didn't use 6 tubes of that stuff- could've bought a TON of Gorilla Glue for the same price!
Great stuff- works ok, but still not nearly as good as Gorilla Glue. Trust me, it's 100x better than anything else out there for foam. After my column project, I'll never use anything else. I bought the largest size I could. This stuff ROCKS.
Make sure you read the directions on it tho. You have to wet one or both sides of your project with a spray of water (just get it damp), then a VERY THIN layer of glue. It doesn't take much! This stuff turns into foam and expands as it dries! Try it once, you'll be a believer.