Follow up...I asked Mike Mather about this at the DSI class yesterday. He said that you should seal the insides of the holes with heavy nail polish or fiberglass resin, and if possible use rubber washers against the helmet in addition to the normal mounting hardware. He also said that due to the fibrous nature of the helmet, it would eventually weaken where the hole was drilled, esp. if subjected to a lot of from in the facemask.
I think I'm going to go ahead and do this with mine. It's an extra helmet and since I rarely flip creeking, I think as along as I don't crush the helmet in my gear bag, it should last for a good long while. I'll report back whenever I get it done.
Join up, suckas.
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