3/8" fasteners seem like waaay overkill. If you got anywhere near close to the fastener strength you would tear out. I was actually thinking about the 8-32 size, total length is a little over 3/8". You should not have much "up" force. I am imagining you are mostly doing sheet goods? Seems better to have more smaller fasteners than fewer larger ones.
I'm thinking that even with the zinc based inserts, if they wear out, or you cut into some, you can just pull them out and replace.
I'm thinking that even with the zinc based inserts, if they wear out, or you cut into some, you can just pull them out and replace.