A lot of builders use the waterbased but only *AFTER* stripping off the paper. for the stripped foam it's used as a poor-to-fair surface skin, a good primer coat, or an excellent lamination glue (be sure to compress the pieces for *at least* 12 hrs)
If you want to build using unstripped foam board, waterbased cannot be used, since it will cause the paper to warp and separate from the board.
All of FT's builds are with the paper left on, so for a FT build, use the oil-based.
Hot glue edgings and joints are pretty nice, but take some skill and a quick hand to apply, squeegee, and clean up -- all before the glue cools and all without getting a second degree burn :black_eyed: It's not a bad technique, but practice a couple of times on a long scrap piece before you try it on your airframe-in-progress