Very nice! Instead of going the bondo route on the next one, you should look into a sculpting putty or clay that cures on its own. I used Free Form Air putty for my ME Terminus helmet. That helmet has a lot of sharp angles and I found the putty allowed me to fine-tune areas and exaggerate certain angles. It also doubles as a fiberglass agent and is highly malleable for several hours after application so there is no need to mess around with FG. Plus, it doesn't give off the fumes bondo does and you can apply it indoors. They also make another called Free Form Earth, which is more dense than the Air version, and I think you might have a better outcome using it for your mask since it is round. Of course it will require a little more application time as opposed to just slapping on bondo, but you won't have a problem sanding it down like you would with bondo. If you do decide to stick with bondo, I'd suggest using the pro Gold series because it is easier to sand than the original. Keep us updated. I love what you have so far.