Plastic putties are great for thinner seams. When the gap is a little wider i use clear coat over it to seal it before painting. For nmf you seal it with thin superglue and it’s invisible. People love it because it doesn’t require sanding. Always great when you want to avoid sanding away a bunch of hard to recreate rivets and panel lines.
Myself i use the Perfect Plastic Putty. I think like everything else in this hobby it has specific uses, not an all purpose do everything solution.
Love your caulking comparison! A buddy and i were talking a couple months ago and he said he uses drywall putty as that’s really all these are
I am sure it has it's uses, just not for filling gaps. Probably makes some nice zimmerit, seat cusion, etc...
