Yes,
It works great! I just did the same thing with my AP ANH armor, by repairing the edges, after ironing them (to give some thickness to it). The edges looked pretty gnarly after ironing them, melted and cracked. So I applied the ABS paste on and around the edges, filled in all the cracks. So I had more to work with, when sanding it down. But be careful using it on thinner parts of your armor, as it will melt through the stuff, and warp the surface. I had that very situation with my helmet. Now I have to fix that! Probably with some bondo, then sand, and repaint the thing. What a pain!
Jess