Mal H and Fatelvis:
NRA Highpower rules do not state that eye protection is mandatory. Luckily, they are not trying to dictate what a person does for their own safety yet. To me, its just like a helmet law...and should not be a matter covered under rules or laws.
Anyway, lemme climb off my soapbox...ehh, there we go.
I have been shooting Highpower for the last year without safety glasses. So far, I haven't found a set that I can see through when the rifle is mounted. I recently went to a shooter-friendly optical shop and I'm working on a solution, and I hope things work out.
Having shot IDPA and IPSC in the past, I'll say this: You stand a much better chance of getting by in HP without the glasses than you do in pistol matches (where I ALWAYS wore safety glasses). In fact, you're probably statistically in greater danger in the pits then on the line due to target frames being hit and so on. Your biggest fear on the line is if yours or another's rifle blows up. That's a pretty rare occurance, but its something to think about.
All too often I have tried to use a pair of glasses on the line, and before the first shot they got tossed. I hope my optometrist-type can help me out. If so, I'll let you know what brand worked for me.
Two things I've found were the most important factors to me. #1, they went VERY high above my eyebrows so that I can see through that part of my range of eyesight and #2 they stay VERY close to my face. I don't want to replace the glasses after every match because of a marked up lens from my rear sight. I know many guys who have ruined glasses because of this, and I've gotten sight black on my eyebrow from my rear sight before. If you're not shooting an AR for HP you won't understand that last one.